Functionalized Nanomaterial-Based Electrochemical Sensors: Principles, Fabrication Methods, and Applications 0128237880, 9780128237885

Functionalized Nanomaterial-Based Electrochemical Sensors: Principles, Fabrication Methods, and Applications provides a

371 75 72MB

English Pages 610 [612] Year 2022

Report DMCA / Copyright

DOWNLOAD PDF FILE

Table of contents :
Front Cover
Functionalized Nanomaterial-Based Electrochemical Sensors: Principles, Fabrication Methods, and Applications
Copyright
Contents
Contributors
Preface
Section A: Modern perspective in electrochemical-based sensors: Functionalized nanomaterials (FNMs)
1 Functionalized nanomaterial-based electrochemical sensors: A sensitive sensor platform
1.1 Introduction
1.2 Quantum-Dot nanomaterial
1.3 Gold nanoparticles
1.4 Carbon-based materials
1.5 Multiwalled nanotubes
1.6 Graphene
1.7 Carbon nanoparticle-based electrochemical sensor
1.8 Magnetic nanoparticles
1.9 Zinc oxide nanotubes
1.10 Nickel oxide nanoparticles and carbon black
1.11 Conclusion
References
2 Recent progress in the graphene functionalized nanomaterial-based electrochemical sensors
2.1 Introduction
2.2 Advantages of graphene-based biosensor
2.3 Preparation of graphene-based biosensor
2.4 Graphene biosensor for glucose and dopamine
2.5 DNA-based biosensing
2.6 Graphene biosensor for protein biomarkers
2.7 Hb biosensor
2.8 Cholesterol biosensor
2.9 GN based biosensor for bacteria
2.10 Conclusion
References
Section B: Fabrication of functionalized nanomaterial-based electrochemical sensors platforms
3 Application of hybrid nanomaterials for development of electrochemical sensors
3.1 Introduction
3.2 SiO 2 /MWCNTs, SiO 2 /MWCNTs/AgNPS, and GO/Sb 2 O 5
3.3 Carbon dots/Fe 3 O 4 and rGO/carbon dots
3.4 rGO/carbon dots/AuNPs
3.5 Conclusion
Websites
References
4 Biofunctionalization of functionalized nanomaterials for electrochemical sensors
4.1 Introduction
4.2 Biosensors
4.2.1 Electrochemical biosensors
4.2.2 Sensor applications of nanomaterials
4.2.3 Biofunctionalization of nanomaterials
4.2.4 Applications in electrochemical sensors
4.3 Conclusion
References
Section C: Functionalized carbon nanomaterial-based electrochemical sensors
5 Functionalized carbon nanomaterials in electrochemical detection
5.1 Introduction
5.1.1 General overview
5.1.2 Carbon nanotubes (CNTs) and carbon nanofibers (CNFs)
5.1.3 Functionalization of CNTs
5.1.4 Graphene
5.1.4.1 Graphene is a material with great potential
5.1.4.2 Properties of graphene
5.2 Functionalization of carbon materials
5.2.1 Need and importance of functionalization of carbon materials
5.2.2 Types of functionalization
5.2.2.1 Activation method
Functionalization of activated carbons
5.2.2.2 Hydrothermal method
5.2.2.3 Immobilization, direct and in situ methods
5.2.2.4 Direct method
5.2.2.5 Thermal annealing
5.2.2.6 Electrospinning method
5.2.2.7 In situ method
5.3 Applications of functionalized carbon materials in electrochemical biosensors
5.3.1 Applications of modified electrodes in electrochemical biosensors
5.3.2 Carbon materials as modifiers
5.3.3 Fullerene modified electrodes
5.3.4 Carbon nanotubes in electrochemical sensors
5.3.5 Graphene-based materials in the electrochemical sensor
5.3.6 Role of carbon/graphene quantum dots in electrochemical biosensors
5.3.7 Carbon nanofibers as electroactive materials in electrochemical sensors
Acknowledgment
References
6 Functionalized carbon material-based electrochemical sensors for day-to-day applications
6.1 Introduction
6.2 Electrochemical biosensors
6.2.1 Amperometric biosensors
6.2.2 Potentiometric biosensors
6.2.3 Impedance biosensors
6.2.4 Voltammetric biosensors
6.3 Supercapacitors
6.4 Gas sensors
6.5 Wearable electronic devices
6.6 Piezoelectric sensors
6.7 Conclusion
References
Section D: Noble metals, non-noble metal oxides and non-carbon-based electrochemical sensors
7 Noble metals and nonnoble metal oxides based electrochemical sensors
7.1 Introduction
7.2 Synthesis of noble metal and nonnoble metal nanoparticles
7.2.1 Top-down methods
7.2.2 Bottom-up methods
7.3 Noble metal-based electrochemical sensors
7.3.1 Gold nanoparticles
7.3.2 Silver nanoparticles
7.3.3 Platinum nanoparticles
7.3.4 Palladium nanoparticles
7.3.5 Application of noble metal-based electrochemical sensors
7.3.5.1 Glucose detection
7.3.5.2 Hydrogen peroxide sensors
7.3.5.3 Environmental applications
7.3.5.4 Medical applications
7.4 Nonnoble metal oxides based electrochemical sensors
7.4.1 Properties of nonnoble metal oxides
7.4.2 Application of nonnoble metal oxides based electrochemical sensors
7.5 Conclusion
References
Section E: Functionalized nanomaterial-based electrochemical based sensors for environmental applications
8 Functionalized nanomaterial-based environmental sensors: An overview
8.1 Introduction
8.2 Noble metal nanomaterials
8.2.1 Gold nanomaterials
8.2.2 Silver nanoparticles
8.2.3 Platinum nanoparticles
8.2.4 Palladium nanoparticles
8.3 Metal oxide nanomaterials
8.4 Carbon nanomaterials
8.4.1 Carbon dots
8.4.2 Carbon nanotubes
8.4.3 Graphene
8.5 Polymer nanomaterials
8.6 Conclusions and perspectives
References
9 Advantages and limitations of functionalized nanomaterials based electrochemical sensors environmental monitoring
9.1 Introduction
9.2 Advantages
9.3 Limitations
9.4 Conclusions and future outlooks
References
Section F: Functionalized nanomaterial-based electrochemical sensors technology for food and beverages applicatio ...
10 Attributes of functionalized nanomaterial-based electrochemical sensors for food and beverage analysis
10.1 Introduction
10.2 Properties of electrochemical sensor in food and beverage analysis
10.2.1 Nanobiosensors
10.3 EC sensors based on functionalized nanomaterials
10.3.1 Carbon-based nanomaterials
10.3.2 Metal and metal oxide nanomaterials
10.4 Additives and contaminants
10.5 Pesticides
10.6 Conclusion and future perspective
References
11 The use of FNMs-based electrochemical sensors in the food and beverage industry
11.1 Introduction
11.2 Food and beverage contamination
11.2.1 Food additives
11.2.2 Heavy metals
11.2.3 Inorganic anions and compounds
11.2.4 Phenolic compounds
11.2.5 Pesticides
11.2.6 Toxins
11.2.7 Pathogen
11.3 Functionalized nanomaterials for sensing in the food and beverage industry
11.3.1 Metal (oxide) based functionalized nanomaterial
11.3.2 Carbon based functionalized nanomaterials
11.3.2.1 Carbon nanotube
11.3.2.2 Graphene materials
11.4 Conclusions and perspectives
References
12 Trends in functionalized Ł NMs-based electrochemical sensors in the food and beverage industry
12.1 Introduction
12.2 Sensor applications of NMs in the food industry
12.3 Reliability problems of NMs for electrochemical sensor applications in food analysis
12.4 Conclusion
References
Section G: Functionalized nanomaterial-based electrochemical sensors for point-of-care applications
13 Functionalized nanomaterial-based medical sensors for point-of-care applications: An overview
13.1 Introduction
13.2 0D (spherical) nanomaterials
13.2.1 Noble metal nanoparticles
13.2.1.1 Gold nanoparticles
13.2.1.2 Silver nanoparticles
13.2.1.3 Platinum nanoparticles
13.2.2 Magnetic nanoparticles
13.2.3 Quantum dots
13.2.4 Carbon-based dots
13.3 One-dimensional nanomaterials
13.3.1 The synthesis of 1D nanomaterials
13.3.1.1 Template-directed nanowire synthesis
13.3.1.2 Electrochemical deposition
13.3.1.3 Pressure injection
13.3.1.4 Sol-gel deposition
13.3.1.5 Vapor phase growth
13.3.1.6 Vapor-solid mechanism
13.3.1.7 Carbothermal growth
13.3.1.8 Solution-based growth
13.3.1.9 Hydrothermal and solvothermal methods
13.3.2 Types of 1D nanomaterials
13.3.2.1 Nanotubes
13.3.2.2 Nanowires
13.3.2.3 Nanorods
13.3.2.4 Carbon nanorods
13.3.2.5 ZnO nanorods
13.3.2.6 Gold nanorods
13.3.2.7 Magnetic nanorods
13.4 Two-dimensional nanomaterials
13.4.1 Graphene
13.4.2 Boron nitride (BN)
13.4.3 Phosphorene
13.4.4 Transition metal dichalcogenides (TMDs)
13.4.5 MXene
13.5 Three-dimensional nanomaterials
13.6 Conclusion and future perspective
References
14 Functionalized nanomaterial- based electrochemical sensors for point-of-care devices
14.1 Introduction
14.2 Electrochemical sensors
14.3 Applications of electrochemical sensors
14.3.1 History of nanotechnology for life sciences
14.3.2 Functionalized nanomaterials-based electrochemical sensors
14.4 The use of functionalized nanomaterials-based electrochemical sensors in point-of-care diagnostics
14.5 Conclusions
Acknowledgment
References
15 Current trends of functionalized nanomaterial-based sensors in point-of-care diagnosis
15.1 Introduction
15.2 Methods of functionalization of nanomaterials
15.2.1 Biological method
15.2.2 Chemical method
15.2.3 Physical method
15.3 Point-of-care diagnostics
15.4 Conclusion
References
Section H: Health, safety, and regulations issues of functionalized nanomaterials
16 Current status of environmental, health, and safety issues of functionalized nanomaterials
16.1 Introduction
16.2 Environmental health and hazards
16.2.1 Categories of environmental health hazards
16.3 Opportunities and challenges
16.3.1 The science of EHS research
16.3.2 Importance of addressing EHS issues
16.3.3 Exposure of hazards and its distribution
16.3.4 Restricted or absence of information ought to be finished with the followings
16.3.5 End for the danger evaluation
16.3.6 Distinguishing proof of human dangers
16.3.7 Ecological openness
16.3.8 Safety precautions to avoid risks
References
17 Functionalized metal and metal oxide nanomaterial-based electrochemical sensors
17.1 Introduction to sensors
17.2 Working principle and classification of electrochemical sensors
17.3 Applications of electrochemical sensors
17.4 Carbon nanomaterials-based electrochemical sensors
17.5 Metallic nanoparticles based electrochemical sensors
17.6 Metallic oxide nanoparticles based electrochemical sensors
17.7 Conclusion
17.8 Challenges and prospects
References
18 Functionalized nanomaterials and workplace health and safety
18.1 Introduction
18.2 Functionalized nanomaterials
18.2.1 Physicochemical effects of toxicity of nanomaterials
18.2.1.1 Size
18.2.1.2 Shape
18.2.1.3 Surface area
18.2.1.4 Aggregation/agglomeration
18.2.1.5 Crystallinity
18.2.1.6 Chemical composition
18.2.1.7 Surface charge and modification
18.2.1.8 Solubility
18.2.2 Ways of exposure to nanomaterials
18.2.2.1 Dermal absorption
18.2.2.2 Pulmonary absorption
18.2.2.3 Eye absorption
18.2.3 Risk assessment and measures that can be taken
18.2.3.1 Risk assessment
18.2.3.2 Risk control
18.3 Conclusion
References
19 Layer-by-layer nanostructured films for electrochemical sensors fabrication
19.1 Introduction
19.2 Layer-by-layer technique
19.3 LbL electrochemical sensors
19.3.1 Potentially toxic metals detection
19.3.2 Pharmaceuticals and personal care products
19.3.3 Pesticides
19.4 LbL electrochemical biosensors
19.4.1 LbL-assembled electrochemical immunosensors
19.4.2 LbL-assembled electrochemical enzymatic sensors
19.4.3 LbL-assembled electrochemical nucleic acid-based sensors
19.5 Final remarks
Acknowledgments
References
Section I: Economics and commercialization of functionalized nanomaterial-based electrochemical sensors
20 Fabrication of functionalized nanomaterial-based electrochemical sensors’ platforms
20.1 Introduction
20.2 Environmental sensors
20.3 Cell-based sensor
20.4 COVID-19 biosensors
References
21 Advantages and limitations of functionalized graphene-based electrochemical sensors for environmental monitoring
21.1 General aspects
21.2 Graphene functionalization
21.3 Functionalized graphene-based electrochemical sensors
21.4 Environmental applications
21.4.1 Pharmaceuticals
21.4.2 Pesticides
21.4.3 Heavy metals
21.5 Concluding remarks and perspectives
Acknowledgments
Thematic websites
References
22 TiO 2 nanotube arrays grafted with metals with enhanced electroactivity for electrochemical sensors and devices
22.1 Introduction
22.2 TiO 2 nanotubes
22.2.1 Anodic oxidation and growth
22.2.2 Factors affecting ordering and structure of TiO 2 nanotubes
22.3 Grafting of noble metals and nonnoble materials on anodic TiO 2 nanotubes
22.4 Electrochemical applications of metal/TiO 2 NTs based sensors
22.4.1 Energy
22.4.1.1 Methanol detection
22.4.1.2 Ethanol detection
22.4.1.3 Borohydride detection
22.4.2 Biosensing
22.4.2.1 Glucose detection
22.4.2.2 Ascorbic acid detection
22.4.2.3 Dopamine detection
22.5 Summary and outlook
References
Section J: Future of functionalized nanomaterial-based electrochemical sensors
23 Functionalized carbon nanomaterial-based electrochemical sensors: Quick look on the future of fitness
23.1 Introduction
23.2 Carbon-nanotube-based electrochemical sensors
23.2.1 Nonenzymatic approach
23.2.2 Enzymatic approach
23.3 Graphene-based electrochemical sensors
23.3.1 Nonenzymatic approach
23.3.2 Enzymatic approach
23.4 Carbon nanodots
23.5 Other carbon functional materials
23.6 Carbon nanomaterials in wearable sensors and future scope
References
Index
Back Cover
Recommend Papers

Functionalized Nanomaterial-Based Electrochemical Sensors: Principles, Fabrication Methods, and Applications
 0128237880, 9780128237885

  • 0 0 0
  • Like this paper and download? You can publish your own PDF file online for free in a few minutes! Sign Up
File loading please wait...
Citation preview

Functionalized Nanomaterial-Based Electrochemical Sensors

This page intentionally left blank

Woodhead Publishing Series in Electronic and Optical Materials

Functionalized Nanomaterial-Based Electrochemical Sensors Principles, Fabrication Methods, and Applications

Edited by

Chaudhery Mustansar Hussain

Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, NJ, United States

Jamballi G. Manjunatha

Department of Chemistry, FMKMC College, Constituent College of Mangalore University, Madikeri, Karnataka, India

An imprint of Elsevier

Woodhead Publishing is an imprint of Elsevier The Officers’ Mess Business Centre, Royston Road, Duxford, CB22 4QH, United Kingdom 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, United States The Boulevard, Langford Lane, Kidlington, OX5 1GB, United Kingdom Copyright © 2022 Elsevier Ltd. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/ permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein). Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein. Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library ISBN: 978-0-12-823788-5 ISBN: 978-0-12-824185-1 For information on all Woodhead publications visit our website at https://www.elsevier.com/books-and-journals

Publisher: Matthew Deans Acquisitions Editor: Kayla Dos Santos Editorial Project Manager: John Leonard Production Project Manager: Surya Narayanan Jayachandran Cover Designer: Victoria Pearson Typeset by STRAIVE, India

Contents

Contributorsxiii Preface xix

Section A  Modern perspective in electrochemical-based sensors: Functionalized nanomaterials (FNMs) 1 1 Functionalized nanomaterial-based electrochemical sensors: A sensitive sensor platform Shashanka Rajendrachari and Dileep Ramakrishna 1.1 Introduction 1.2 Quantum-Dot nanomaterial 1.3 Gold nanoparticles 1.4 Carbon-based materials 1.5 Multiwalled nanotubes 1.6 Graphene 1.7 Carbon nanoparticle-based electrochemical sensor 1.8 Magnetic nanoparticles 1.9 Zinc oxide nanotubes 1.10 Nickel oxide nanoparticles and carbon black 1.11 Conclusion References 2 Recent progress in the graphene functionalized nanomaterial-based electrochemical sensors Rajat Kumar Pandey, Deepak Kapoor, Deepak Kumar, Rajiv Tonk, Shankramma Kalikeri, Srilatha Rao, and Gururaj Kudur Jayaprakash 2.1 Introduction 2.2 Advantages of graphene-based biosensor 2.3 Preparation of graphene-based biosensor 2.4 Graphene biosensor for glucose and dopamine 2.5 DNA-based biosensing 2.6 Graphene biosensor for protein biomarkers 2.7 Hb biosensor 2.8 Cholesterol biosensor 2.9 GN based biosensor for bacteria 2.10 Conclusion References

3 3 4 10 11 11 12 13 13 14 15 18 19 27 27 28 29 29 31 33 33 34 35 35 36

viContents

Section B  Fabrication of functionalized nanomaterial-based electrochemical sensors platforms 3 Application of hybrid nanomaterials for development of electrochemical sensors Thiago C. Canevari 3.1 Introduction 3.2 SiO2/MWCNTs, SiO2/MWCNTs/AgNPS, and GO/Sb2O5 3.3 Carbon dots/Fe3O4 and rGO/carbon dots 3.4 rGO/carbon dots/AuNPs 3.5 Conclusion Websites References 4 Biofunctionalization of functionalized nanomaterials for electrochemical sensors Muhammed Bekmezci, Ramazan Bayat, Vildan Erduran, and Fatih Sen 4.1 Introduction 4.2 Biosensors 4.3 Conclusion References

Section C  Functionalized carbon nanomaterial-based electrochemical sensors 5 Functionalized carbon nanomaterials in electrochemical detection Sankararao Mutyala, P. Hari Krishna Charan, Rajendran Rajaram, and K. Naga Mahesh 5.1 Introduction 5.2 Functionalization of carbon materials 5.3 Applications of functionalized carbon materials in electrochemical biosensors Acknowledgment References 6 Functionalized carbon material-based electrochemical sensors for day-to-day applications Vildan Erduran, Muhammed Bekmezci, Ramazan Bayat, and Fatih Sen 6.1 Introduction 6.2 Electrochemical biosensors 6.3 Supercapacitors 6.4 Gas sensors

39 41 41 41 46 47 51 51 51 55 55 56 64 65

71 73 73 77 82 88 88 97 97 99 103 103

Contentsvii

6.5 Wearable electronic devices 6.6 Piezoelectric sensors 6.7 Conclusion References

Section D  Noble metals, non-noble metal oxides and non-carbon-based electrochemical sensors

103 104 104 105

113

7 Noble metals and nonnoble metal oxides based electrochemical sensors 115 Parisa Nasr-Esfahani and Ali A. Ensafi 7.1 Introduction 115 7.2 Synthesis of noble metal and nonnoble metal nanoparticles 117 7.3 Noble metal-based electrochemical sensors 120 7.4 Nonnoble metal oxides based electrochemical sensors 132 7.5 Conclusion 136 References 137

Section E  Functionalized nanomaterial-based electrochemical based sensors for environmental applications 141 8 Functionalized nanomaterial-based environmental sensors: An overview Ali A. Ensafi, N. Kazemifard, and Z. Saberi 8.1 Introduction 8.2 Noble metal nanomaterials 8.3 Metal oxide nanomaterials 8.4 Carbon nanomaterials 8.5 Polymer nanomaterials 8.6 Conclusions and perspectives References 9 Advantages and limitations of functionalized nanomaterials based electrochemical sensors environmental monitoring Balaji Maddiboyina, OmPrakash Sunaapu, Sandeep Chandrashekharappa, and Gandhi Sivaraman 9.1 Introduction 9.2 Advantages 9.3 Limitations 9.4 Conclusions and future outlooks References

143 143 149 153 155 158 160 160 165 165 168 169 170 170

viiiContents

Section F  Functionalized nanomaterial-based electrochemical sensors technology for food and beverages applications 175 10 Attributes of functionalized nanomaterial-based electrochemical sensors for food and beverage analysis A.H. Sneharani 10.1 Introduction 10.2 Properties of electrochemical sensor in food and beverage analysis 10.3 EC sensors based on functionalized nanomaterials 10.4 Additives and contaminants 10.5 Pesticides 10.6 Conclusion and future perspective References 11 The use of FNMs-based electrochemical sensors in the food and beverage industry Masoud Reza Shishehbore and Mohadeseh Safaei 11.1 Introduction 11.2 Food and beverage contamination 11.3 Functionalized nanomaterials for sensing in the food and beverage industry 11.4 Conclusions and perspectives References 12 Trends in functionalized ­NMs-based electrochemical sensors in the food and beverage industry Ramazan Bayat, Muhammed Bekmezci, Vildan Erduran, and Fatih Sen 12.1 Introduction 12.2 Sensor applications of NMs in the food industry 12.3 Reliability problems of NMs for electrochemical sensor applications in food analysis 12.4 Conclusion References

Section G  Functionalized nanomaterial-based electrochemical sensors for point-of-care applications 13 Functionalized nanomaterial-based medical sensors for point-of-care applications: An overview Ali A. Ensafi, Z. Saberi, and N. Kazemifard 13.1 Introduction 13.2 0D (spherical) nanomaterials 13.3 One-dimensional nanomaterials

177 177 180 182 190 193 193 194 207 208 210 213 244 245 261 261 262 268 270 270

275 277 277 280 288

Contentsix

13.4 Two-dimensional nanomaterials 13.5 Three-dimensional nanomaterials 13.6 Conclusion and future perspective References 14 Functionalized nanomaterial-based electrochemical sensors for point-of-care devices Hilmi Kaan Kaya, Tahsin Çağlayan, and Filiz Kuralay 14.1 Introduction 14.2 Electrochemical sensors 14.3 Applications of electrochemical sensors 14.4 The use of functionalized nanomaterials-based electrochemical sensors in point-of-care diagnostics 14.5 Conclusions Acknowledgment References 15 Current trends of functionalized nanomaterial-based sensors in point-of-care diagnosis S. Nandini, S. Nalini, S. Bindhu, S. Sandeep, C.S. Karthik, K.S. Nithin, P. Mallu, and J.G. Manjunatha 15.1 Introduction 15.2 Methods of functionalization of nanomaterials 15.3 Point-of-care diagnostics 15.4 Conclusion References

Section H  Health, safety, and regulations issues of functionalized nanomaterials 16 Current status of environmental, health, and safety issues of functionalized nanomaterials A. Priyadharsan, S. Shanavas, S. Boobas, Tansir Ahamad, R. Acevedo, P.M. Anbarasan, and R. Ramesh 16.1 Introduction 16.2 Environmental health and hazards 16.3 Opportunities and challenges References 17 Functionalized metal and metal oxide nanomaterial-based electrochemical sensors H.C. Ananda Murthy, Ararso Nagari Wagassa, C.R. Ravikumar, and H.P. Nagaswarupa 17.1 Introduction to sensors 17.2 Working principle and classification of electrochemical sensors

294 297 298 299 309 309 311 314 320 325 326 326 337 337 339 343 349 350

355 357 357 358 361 366 369 369 370

xContents

17.3 Applications of electrochemical sensors 17.4 Carbon nanomaterials-based electrochemical sensors 17.5 Metallic nanoparticles based electrochemical sensors 17.6 Metallic oxide nanoparticles based electrochemical sensors 17.7 Conclusion 17.8 Challenges and prospects References 18 Functionalized nanomaterials and workplace health and safety Vildan Erduran, Muhammed Bekmezci, Ramazan Bayat, Zübeyde Bayer Altuntaş, and Fatih Sen 18.1 Introduction 18.2 Functionalized nanomaterials 18.3 Conclusion References

372 373 379 383 387 387 388 393 393 394 400 401

19 Layer-by-layer nanostructured films for electrochemical sensors fabrication 407 Celina M. Miyazaki, Flavio M. Shimizu, and Marystela Ferreira 19.1 Introduction 408 19.2 Layer-by-layer technique 410 19.3 LbL electrochemical sensors 414 19.4 LbL electrochemical biosensors 424 19.5 Final remarks 433 Acknowledgments 433 References 434

Section I  Economics and commercialization of functionalized nanomaterial-based electrochemical sensors 443 20 Fabrication of functionalized nanomaterial-based electrochemical sensors’ platforms Waleed A. El-Said, Naeem Akhtar, and Mostafa M. Kamal 20.1 Introduction 20.2 Environmental sensors 20.3 Cell-based sensor 20.4 COVID-19 biosensors References 21 Advantages and limitations of functionalized graphene-based electrochemical sensors for environmental monitoring Álvaro Torrinha, Thiago M.B.F. Oliveira, Francisco W.P. Ribeiro, Simone Morais, Adriana N. Correia, and Pedro de Lima-Neto 21.1 General aspects 21.2 Graphene functionalization

445 445 451 462 462 465 487 487 489

Contentsxi

21.3 Functionalized graphene-based electrochemical sensors 21.4 Environmental applications 21.5 Concluding remarks and perspectives Acknowledgments Thematic websites References 22 TiO2 nanotube arrays grafted with metals with enhanced electroactivity for electrochemical sensors and devices Hamed Cheshideh, Elnaz Moslehifard, and Farzad Nasirpouri 22.1 Introduction 22.2 TiO2 nanotubes 22.3 Grafting of noble metals and nonnoble materials on anodic TiO2 nanotubes 22.4 Electrochemical applications of metal/TiO2 NTs based sensors 22.5 Summary and outlook References

Section J  Future of functionalized nanomaterial-based electrochemical sensors 23 Functionalized carbon nanomaterial-based electrochemical sensors: Quick look on the future of fitness Puchakayala Swetha and Yaamini Mohan 23.1 Introduction 23.2 Carbon-nanotube-based electrochemical sensors 23.3 Graphene-based electrochemical sensors 23.4 Carbon nanodots 23.5 Other carbon functional materials 23.6 Carbon nanomaterials in wearable sensors and future scope References

491 492 510 511 512 512 521 521 522 530 536 548 548

555 557 557 558 560 566 570 571 572

Index 579

This page intentionally left blank

Contributors R. Acevedo  Faculty of Engineering and Technology, San Sebastian University, Santiago, Chile Tansir Ahamad Department of Chemistry, College of Science, King Saud University, Riyadh, Saudi Arabia Naeem Akhtar Interdisciplinary Research Center in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore, Pakistan Zübeyde Bayer Altuntaş  Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya, Turkey H.C. Ananda Murthy Department of Applied Chemistry, School of Natural Science, Adama Science and Technology University, Adama, Ethiopia P.M. Anbarasan  Nano and Hybrid Materials Laboratory, Department of Physics, Periyar University, Salem, Tamil Nadu, India Ramazan Bayat  Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya; Department of Materials Science & Engineering, Faculty of Engineering, Dumlupınar University, Kütahya, Turkey Muhammed Bekmezci  Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya; Department of Materials Science & Engineering, Faculty of Engineering, Dumlupınar University, Kütahya, Turkey S. Bindhu Department of Chemistry, SJCE, JSS Science and Technology University, Mysuru, Karnataka, India S. Boobas Department of Physics, Sri Vasavi College, Bhavani, Tamil Nadu, India Tahsin Çağlayan  Defense Industries Research and Development Institute, The Scientific and Technological Research Council of Turkey, Ankara, Turkey Thiago C. Canevari Chemistry Course, Engineering School, Mackenzie Presbyterian University, São Paulo, SP, Brazil Sandeep Chandrashekharappa  Institute for Stem Cell Biology and Regenerative Medicine (InStem), Bangalore, Karnataka, India

xivContributors

Hamed Cheshideh  Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran; Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan Adriana N. Correia Departamento de Química Analítica e Físico-Química, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil Pedro de Lima-Neto Departamento de Química Analítica e Físico-Química, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil Waleed A. El-Said Department of Chemistry, Faculty of Science, Assiut University, Assiut, Egypt; Department of Chemistry, College of Science, University of Jeddah, Jeddah, Saudi Arabia Ali A. Ensafi Department of Chemistry, Isfahan University of Technology, Isfahan, Iran; Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States Vildan Erduran  Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya; Department of Materials Science & Engineering, Faculty of Engineering, Dumlupınar University, Kütahya, Turkey Marystela Ferreira  Centre of Science and Technology for Sustainability, Federal University of São Carlos, Sorocaba, São Paulo, Brazil P. Hari Krishna Charan Department of Chemistry, Aditya Institute of Technology and Management, Srikakulam, Andhra Pradesh, India Gururaj Kudur Jayaprakash  School of Advanced Chemical Sciences, Shoolini University, Solan, Himachal Pradesh, India Shankramma Kalikeri  Division of Nanoscience and Technology, Department of Water and Health (Faculty of Life Sciences), JSS Academy of Higher Education & Research (Deemed to be University), Mysore, Karnataka, India Mostafa M. Kamal Department of Chemistry, Faculty of Science, Assiut University, Assiut, Egypt Deepak Kapoor  Department of Pharmaceutical Chemistry, Delhi Pharmaceutical Sciences Research University, New Delhi, India C.S. Karthik  Department of Chemistry, SJCE, JSS Science and Technology University, Mysuru, Karnataka, India

Contributorsxv

Hilmi Kaan Kaya Department of Chemistry, Faculty of Science, Hacettepe University, Ankara, Turkey N. Kazemifard Department of Chemistry, Isfahan University of Technology, Isfahan, Iran Deepak Kumar  School of Pharmaceutical Sciences, Shoolini University, Solan, Himachal Pradesh, India Filiz Kuralay  Department of Chemistry, Faculty of Science, Hacettepe University, Ankara, Turkey Balaji Maddiboyina  Department of Pharmacy, Vishwabharathi College of Pharmaceutical Sciences, Guntur, Andhra Pradesh, India P. Mallu Department of Chemistry, SJCE, JSS Science and Technology University, Mysuru, Karnataka, India J.G. Manjunatha Department of Chemistry, FMKMC College, Constituent College of Mangalore University, Madikeri, Karnataka, India Celina M. Miyazaki  Centre of Science and Technology for Sustainability, Federal University of São Carlos, Sorocaba, São Paulo, Brazil Yaamini Mohan  School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India Simone Morais  REQUIMTE-LAQV, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Porto, Portugal Elnaz Moslehifard  Department of Prosthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran Sankararao Mutyala Nanosol Energy Pvt Ltd, Hyderabad, Telangana, India K. Naga Mahesh Nanosol Energy Pvt Ltd, Hyderabad, Telangana, India H.P. Nagaswarupa  Department of Studies in Chemistry, Davangere University, Shivagangothri, Davangere, Karnataka, India S. Nalini  Department of Biochemistry, Bangalore City University, Bengaluru, Karnataka, India

xviContributors

S. Nandini  Department of Biochemistry, Bangalore City University, Bengaluru, Karnataka, India Farzad Nasirpouri  Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran Parisa Nasr-Esfahani Department of Chemistry, Isfahan University of Technology, Isfahan, Iran K.S. Nithin Department of Chemistry, The National Institute of Engineering, Mysuru, Karnataka, India Thiago M.B.F. Oliveira  Centro de Ciência e Tecnologia, Universidade Federal do Cariri, Juazeiro do Norte, Ceará, Brazil Rajat Kumar Pandey  School of Pharmaceutical Sciences, Shoolini University, Solan, Himachal Pradesh, India A. Priyadharsan  Department of Physics, E.R.K. Arts and Science College, Erumiyampatti, Tamil Nadu, India Rajendran Rajaram Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, India Shashanka Rajendrachari Department of Metallurgical and Materials Engineering, Bartin University, Bartin, Turkey Dileep Ramakrishna Department of Chemistry, School of Engineering, Presidency University, Bangalore, India R. Ramesh Department of Physics, Periyar University, Salem, Tamil Nadu, India Srilatha Rao  Department of Chemistry, Nitte Meenakshi Institute of Technology, Bangalore, Karnataka, India C.R. Ravikumar  Research Centre, Department of Science, East West Institute of Technology, VTU, Bangalore, Karnataka, India Francisco W.P. Ribeiro Instituto de Formação de Educadores, Universidade Federal do Cariri, Brejo Santo, Ceará, Brazil Z. Saberi Department of Chemistry, Isfahan University of Technology, Isfahan, Iran Mohadeseh Safaei Department of Chemistry, Yazd Branch, Islamic Azad University, Yazd, Iran

Contributorsxvii

S. Sandeep Department of Chemistry, SJCE, JSS Science and Technology University, Mysuru, Karnataka, India Fatih Sen Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya, Turkey S. Shanavas Nano and Hybrid Materials Laboratory, Department of Physics, Periyar University, Salem, Tamil Nadu, India Flavio M. Shimizu  Department of Applied Physics, “Gleb Wataghin” Institute of Physics (IFGW), University of Campinas (UNICAMP), Campinas, São Paulo, Brazil Masoud Reza Shishehbore  Department of Chemistry, Yazd Branch, Islamic Azad University, Yazd, Iran Gandhi Sivaraman Department of Chemistry, Gandhigram Rural Institute Deemed University, Dindigul, Tamil Nadu, India A.H. Sneharani  DoS in Biochemistry, Jnana Kaveri P.G. Center, Mangalore University, Kodagu, India OmPrakash Sunaapu Department of Chemistry, University College of Engineering, Anna University, Dindigul, Tamil Nadu, India Puchakayala Swetha State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, People’s Republic of China Rajiv Tonk Department of Pharmaceutical Chemistry, Delhi Pharmaceutical Sciences Research University, New Delhi, India Álvaro Torrinha  REQUIMTE-LAQV, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Porto, Portugal Ararso Nagari Wagassa  Department of Applied Chemistry, School of Natural Science, Adama Science and Technology University, Adama, Ethiopia

This page intentionally left blank

Preface

Since the last decade, utility of nanomaterials and functionalized nanostructures has become significant in multidisciplinary fields including biomedical, environmental, food and beverages, textiles, pharmaceutical, cosmetics, agricultural, sensors, energy storage management, electronic materials, etc. Specifically, new methods in the synthesis of functionalized nanomaterials (FNMs) and their applications in different areas of science have been developed. Functionalization of nanomaterials is a method of inserting a particular material onto the surface of the nanomaterial to boost its properties and reduce its toxicity. Functionalized nanomaterials can be synthesized through covalent, noncovalent, grafting, physical methods, etc. They have a great impact on the fabrication of electrochemical sensors and biosensors for the determination of a wide spectrum of molecules, toxic ions, and even disease diagnosis applications. Their real-time applications are extensive due to their unique characteristics like high electrical, thermal, mechanical, and electronic properties and biocompatibility, large surface, etc. Electrochemical sensors and devices are well known for their versatile applications and advantages like simple handling procedure, quick results, high sensitivity and selectivity, low consumption of sample, etc. This book gives the readers a holistic insight into functionalized nanomaterial-based electrochemical sensors from design to application. This book is categorized into several sections: Section A explains “Modern Perspectives in Electrochemical-Based Sensors: Functionalized Nanomaterials (FNMs)”; Section B deals with “Fabrication of Functionalized Nanomaterial-Based Electrochemical Sensor Platforms”; Section C describes “Functionalized Carbon Nanomaterial-Based Electrochemical Sensors”; Section D provides “Noble Metals, Non-Noble Metal Oxides, and Noncarbon-Based Electrochemical Sensors”; Section E conveys “Functionalized Nanomaterial-Based Electrochemical Sensors for Environmental Applications”; Section F emphasizes on “Functionalized Nanomaterial-Based Electrochemical Sensor Technology for Food and Beverage Applications”; Section G focuses on “Functionalized NanomaterialBased Electrochemical Sensors for Point-of-Care Applications”; Section H deals with “Health, Safety, and Regulation Issues for Functionalized Nanomaterials”; Section I describes “Economics and Commercialization of Functionalized NanomaterialBased Electrochemical Sensors”; and Section J explains “Future of Functionalized Nanomaterial-Based Electrochemical Sensors.” The goal of this book is to provide a comprehensive insight from the basic level to the application of FNMs for the fabrication of electrochemical sensors and biosensors. I hope this book will be a great asset to electrochemists, material scientists, college and university graduates, chemists, biologists, pharmacists, engineers,

xxPreface

p­ hysicists, industrial researchers, and analytical scientists. The editor and contributors are eminent researchers and experts from universities and various industries. On behalf of Elsevier, we thank all the authors of this book for their valuable contributions. We are extremely thankful to John Leonard (editorial project manager) at Elsevier for his tremendous support and assistance throughout this assignment. J.G. Manjunatha, Editor 

Section A Modern perspective in electrochemical-based sensors: Functionalized nanomaterials (FNMs)

This page intentionally left blank

Functionalized nanomaterial-based electrochemical sensors: A sensitive sensor platform

1

Shashanka Rajendracharia and Dileep Ramakrishnab a Department of Metallurgical and Materials Engineering, Bartin University, Bartin, Turkey, b Department of Chemistry, School of Engineering, Presidency University, Bangalore, India

1.1 Introduction A great advancement in science and technology as an indispensable technology growth is the use of Nanomaterials and nanotechnology. Nanomaterials are materials that have one of their dimensions less than or equal to 100-nm scale [1–4]. With the advancement in synthetic methodologies, the preparation of a variety of these nanomaterials is permitted with the desired size, surface properties, shape, and other physicochemical properties [5–7]. Moreover, the materials that can be functionalized thus present a great panorama for uniting biological credit and signal transduction mechanisms which lead to the development of novel bioelectronic devices with outstanding sensor properties [8–13]. Nanomaterials usually have a larger surface area and this compliments the improvement in electron-transfer rate [14–17]. Thus, these properties are quite utilized in catalysis, polymer technology, drug delivery, food production, painting, and electrochemical sensing [18]. Electrochemical sensors form a vital subdivision of chemical sensors in which the transduction element is designed from an electrode source [19,20]. It works on the principle of electrochemistry, which is a very influential electroanalytical technique that shows the advantages in terms of high sensitivity, instrument simplicity, portability, easy miniaturization, and is relatively cost-effective [21]. A portable biochemical detection was made possible, very recently, through the use of smartphones assimilated with sensors, such as test trips, sensor chips, and hand-held detectors [22]. The assimilation of these miniaturized devices as sensitive arrays was possible through the application of micro-electro-­mechanical systems and of course nanotechnology [23–25]. Meanwhile, some of the properties of sensors are very high sensitivity, selectivity, and stability, researchers have been pushing a lot of effort on refining these properties. In this case, the incorporation of nanomaterials is playing its role as sensors. Generally, nanomaterials exhibit unique properties and functionalities which can create a promising evolution of the new analytical schemes that are easily triggered to detect various biological molecules [26]. These analytical schemes have been used with numerous sensor programs covering a wide range of nanomaterials and fabrication convolution [27]. A nano-level fabrication of the electrode surface is a gifted platform to develop high-performance electrochemical to detect the target Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00010-7 Copyright © 2022 Elsevier Ltd. All rights reserved.

4

Functionalized Nanomaterial-Based Electrochemical Sensors

analytes [28]. The design of these types of ­nano-level electrode materials focuses on the signal amplification through the catalytic activity and conductivity, facile interactions with chemical and biological reagents, and the immobilization of the functional moieties with precisely designed as signal tags which are prominent in highly selective sensing [29]. Therefore, the fabrication of a functionalized nanomaterial-based electrode is recently progressing with high acceleration. This chapter aims to expose researchers to the success recorded in this area while hoping that the article will stimulate further discoveries in the area of electrochemical sensors using nanomaterials.

1.2 Quantum-Dot nanomaterial Quantum dots are semiconductor nanocrystals in which excitons are confined in all three spatial dimensions. The confinement can be realized by fabricating the semiconductor in a very small size, typically several hundred to thousands of atoms per particle [30,31]. Due to quantum confinement effects, QDs act like artificial atoms, showing controllable discrete energy levels. QDs were first fabricated in the 1980s by Louis E. Brus and the unique properties of these special nano-structures attracted interest from many fields. Quantum-Dot (QD) semiconductor nanocrystals have been reported to be used for the design of multianalyte electrochemical aptamers biosensors with sub picomolar (attomole) detection limit [32]. QDs can be optically excited. When absorbing photons, electrons in QDs gain energy leading to the creation of excitons. An exciton is a bound state of an electron and a quasiparticle called a hole. After relaxation from the excitonic excited state to its lower energy state, the electron and hole recombine (exciton recombination), emitting a photon. The overall process of optical excitation, relaxation of the excited state, recombination of electron and hole, and fluorescent emission is called photoluminescence (PL). The number of photons emitted can be measured as a function of energy, which gives the PL spectrum. Different from many organic dyes, QDs can be excited by many light sources within a large wavelength range, since QDs have continuous and broad absorption spectra. Furthermore, many kinds of QDs can be excited by the same light source and their emission can be easily separated. The emission light spectra of QDs are narrower and more symmetric than conventional organic dyes, making the sensitivity of detection higher than for organic dyes. Due to this property, QDs are attractive fluorophores for biological imaging (biological tagging). The energy gap of excitons in QDs is strongly size dependent. This size-dependent phenomenon is due to the effect of confinement: The smaller QDs have stronger confinement making the energy gap larger. Similarly, a larger size gives a smaller energy gap. Hence, QDs with different emission colors can be made from the same material by changing their size. Hence for larger (small) sizes, the emission is more toward the red (blue). Colloidal QDs, which are synthesized by relatively inexpensive wet chemistry methods, make it possible to have the desired particle size which makes it easy to find QDs with the energy spectrum we need and high quantum yield (number of photons absorbed over the number of photons emitted), even at room temperature. Currently, CdSe or CdTe QDs with a ZnS shell is commonly used and studied. The

Functionalized nanomaterial-based electrochemical sensors

5

Core/Shell structure diminishes chemical damage to the fluorescence core. ZnS is optically transparent to the emission range; therefore, there are no photon losses associated with the shell with visible light emission. A study, as discussed below, is done to show the application of QDs in biological imaging. The aptamer is the RNA or DNA ligand to the target molecule and it was typically attained by a methodology called systematic evolution of ligands by exponential fortification (SELEX) [33]. The aptamers can fix powerfully to a target molecule like an antibody and can be custom-made with a higher degree of efficiency. This is as such used as a powerful tool for proteome analysis [34]. Other advantages are its qualified ease of isolation and modifications united with high stability. The nanocrystals play a very important and significant role in electro diversification of the electrical tags which is one of the requirements for multiplexed bioanalysis. Due to the remarkably low (attomole) detection limit, this can be a consequence of the extensive amplification excellence of the nanoparticle-based electrochemical stripping measurements [35]. Since it is a multianalyte biosensor, four different encoding nanomaterials, CdS, ZnS, CuS, and PbS, were used to differentiate the signals of four targeted DNA. For functioning the aptamer/Quantum-Dot-Based dual-analyte biosensor, a single-step displacement assay was utilized as presented in Scheme 1.1. In the scheme, numerous thiolated aptamers were co-immobilized, along with the binding of similar QD-tagged proteins on the gold substrate (A). This was followed by the addition of sample (B), with the displacement of the tag proteins. This displacement allows the monitoring of remaining nanocrystals through an electrochemical detection source (C). The biosensor was first used for single analyte sensing to evaluate its sensitivity and selectivity. High sensitivity grew from the electrochemical detection is shown in Fig. 1.1A and the calibration plot, presented in Fig. 1.1B represents a rapid drop in the peak current up to 200 ng L− 1 which, in the future, maintained a slower decrease (a characteristic of displacement assays). The detection limit of 20 ng L− 1 (0.5 pM) was recorded between the 20 and 500 ng L− 1 concentration range. Therefore, the biosensor has a considerably lower detection limit (of the order of 3–4) relative to those aptamer biosensors reported previously [36–38]. High reproducibility (relative standard deviation of 5%) was recorded after six consecutive measurements of 100 ng L− 1 thrombin. Dissolution of the QDs (conjugated to the undisplaced protein molecules) was carried out by the addition of HNO3 (100 μL, 0.1 M) and sonication for 1 h. The resulting solution was transferred to a 1 mL electrochemical cell containing 900 μL of acetate buffer (0.1 M, pH 4.6) and 10 ppm mercury (II). Electrochemical stripping detection proceeded after 1 min pretreatment at + 0.6 V, 2 min accumulation at − 1.2 V, and scanning the potential to − 0.25 V [32]. A multianalyte assignment of the biosensor was validated in Fig.  1.2. Here, the dual-analyte detection of thrombin (a) and lysozyme (b) was shown. Comparable reductions in both the metal peaks were a consequence of the simultaneous addition of both thrombin and lysozyme proteins (Fig.  1.2D). This advises that as much as five or six protein targets can be analyzed simultaneously in a single run if there are nonoverlapping metal peaks within a given potential window. CdS nanoparticle-based (another Quantum-Dot) biosensing of sugars established on their interaction with ­surface-functionalized lectins was also presented in Scheme 1.2 [39]. This is done

Scheme 1.1  Operation of the Aptamer/Quantum-Dot-based dual-analyte biosensor involving the displacement of tagged proteins by the target analytes. (A) Mixed monolayer of thiolated aptamers on the gold substrate with the bound protein − QD conjugates; (B) sample addition and displacement of the tagged proteins; (C) dissolution of the remaining captured nanocrystals followed by their electrochemical-stripping detection at a coated glassy carbon electrode. Courtesy: J.A. Hansen, J. Wang, A.-N. Kawde, Y. Xiang, K.V. Gothelf, G. Collins, Quantumdot/aptamer-based ultrasensitive multi-analyte electrochemical biosensor, J. Am. Chem. Soc. 128 (2006) 2228–2229.

Functionalized nanomaterial-based electrochemical sensors

7

Fig. 1.1  (A) Square-wave stripping voltammograms for different concentrations of thrombin: (a) 0, (b) 100, and (c) 500 ng L− 1. (B) The resulting calibration plot. (C) Assessment of the selectivity using nontarget proteins: (a) control (no analyte or interference), (b) 25 μg L− 1 BSA, and (c) 25 μg L− 1 IgG. Courtesy: J.A. Hansen, J. Wang, A.-N. Kawde, Y. Xiang, K.V. Gothelf, G. Collins, Quantumdot/aptamer-based ultrasensitive multi-analyte electrochemical biosensor, J. Am. Chem. Soc. 128 (2006) 2228–2229.

Fig. 1.2  Simultaneous bioelectronic detection of lysozyme and thrombin. Square-wave stripping voltammograms obtained after additions of (A) 0 μg L− 1 protein, (B) 1 μg L− 1 lysozyme, (C) 0.5 μg L− 1 thrombin, and (D) a mixture of 1 μg L− 1 lysozyme (a) and 0.5 μg L− 1 thrombin (b). Conditions as in Fig. 1.1. Courtesy: J.A. Hansen, J. Wang, A.-N. Kawde, Y. Xiang, K.V. Gothelf, G. Collins, Quantumdot/aptamer-based ultrasensitive multi-analyte electrochemical biosensor, J. Am. Chem. Soc. 128 (2006) 2228–2229.

8

Functionalized Nanomaterial-Based Electrochemical Sensors

CdS

CdS

CdS

CdS OH OH

OH OH

OH

S S S S S NHS/EDAC

Au

(a)

Au

(b)

OH

S SSSS

Au

OH OH

OH

i/µA

COOH COOH

S SSSS

(c)

Au

(d) -0.8 -0.6 E/V

Scheme 1.2  Operation of the nanoparticle-based bioelectronic sensor for glycans involving competition of the tagged sugar with the target analytes for the binding sites of the immobilized lectin. (a) Mixed self-assembled monolayer on the gold substrate; (b) covalent immobilization of the lectin; (c) addition of the tagged and untagged sugars; (d) dissolution of the captured nanocrystals, followed by their stripping-voltammetry detection at a mercurycoated glassy carbon electrode. Courtesy: Z. Dai, A.-N. Kawde, Y. Xiang, J.T. La Belle, J. Gerlach, V.P. Bhavanandan, L. Joshi, J. Wang, Nanoparticle-based sensing of glycan–lectin interactions, J. Am. Chem. Soc. 128 (2006) 10018–10019.

by immobilization of lectin (a recognition element for carbohydrates) onto a gold surface. A conflict between a nanocrystal (CdS)-labeled sugar and target sugar for ­carbohydrate-binding sites on lectins was monitored through highly sensitive electrochemical stripping detection of the captured nanocrystal. Thus, the lectin-sugar recognition event yields diverse cadmium stripping voltammetry current peak, in which the size of the same, depends inversely on the level and affinity of the target glycan. An exemplary system with a surface-bound pure Arachis hypogaea (peanut agglutinin, PNA) lectin and various analytes were used in the optimization and testing of the assay. Excellent selectivity for targeted analytes was observed (Fig. 1.3). The sensitivity trend was found consistent with the reported relative attraction of these carbohydrate moieties to PNA lectin (β-d-Gal-[1 → 3], -d-GalNAc > Gal > GalNAc) [40,41]. Fascinatingly, no response was observed even with the larger amounts of nontarget sugars such as glucose and mannose (Fig. 1.3e and f). This proves that the array of Lectin could be a very successful distinguisher of individual sugars [39]. Fig. 1.4D depicts the Square-wave voltammetric signals for different concentrations of the target β-d-Gal-[1 → 3]-d-GalNAc glycan. A distinctly reduced cadmium stripping peaks, consistent with smaller levels of the captured CdStagged sugar, was observed with an increase in the concentration of the target. Incubation time, 60  min. The dissolution of the QDs (conjugated to the ­lectin-bound sugar molecules) was carried out by adding 100 μL nitric acid (0.1 M) and incubating for 60 min. The resulting solution was transferred to the electrochemical cell containing 300 μL of acetate buffer (0.1 M, pH 5.3) and 10 ppm Hg2 +. Electrochemical stripping detection proceeded using an 8 min deposition at − 1.1 V and scanning the potential to − 0.2 V using an amplitude of 25 mV, a potential step of 4, and a frequency of 25 Hz. Concentration of the tagged sugar [CdS-(4aminophenol-β-d-galactopyranoside)] is 800 μg L− 1 [39].

Functionalized nanomaterial-based electrochemical sensors

9

Fig. 1.3  Square-wave voltammetry stripping signals in the presence of (a) “control” solution (no target), (b) 11.1 μM GalNAc, (c) 11.1 μM Gal, (d) 11.1 μM β-d-Gal-[1 → 3]-d-GalNAc, (e) 277 μM glucose, and (f) 277 μM mannose. Courtesy: Z. Dai, A.-N. Kawde, Y. Xiang, J.T. La Belle, J. Gerlach, V.P. Bhavanandan, L. Joshi, J. Wang, Nanoparticle-based sensing of glycan–lectin interactions, J. Am. Chem. Soc. 128 (2006) 10018–10019.

100

a

A

b 0

20

40

100

60

B

50 0

0

20

40

100

c

Current / µA

Decrease percentage / %

0

D

2 µA

50

d

60

C

50 0

–0.8 –0.6 0

5

10

Sugar concentration/µM

Potential/V

Fig. 1.4  Corresponding calibration plots of (A) GalNAc, (B) Gal, and (C) β-d-Gal-[1 → 3]-dGalNAc. (D) Square-wave voltammetry stripping signals in the presence of (a) 0.0, (b) 0.277, (c) 2.77, and (d) 11.1 μM β-d-Gal-[1 → 3]-d-GalNAc. Other conditions, as in Fig. 1.3. Courtesy: Z. Dai, A.-N. Kawde, Y. Xiang, J.T. La Belle, J. Gerlach, V.P. Bhavanandan, L. Joshi, J. Wang, Nanoparticle-based sensing of glycan–lectin interactions, J. Am. Chem. Soc. 128 (2006) 10018–10019.

10

Functionalized Nanomaterial-Based Electrochemical Sensors

The calibration plot shown in Fig.  1.4C shows the detection limit for β-dGal-[1 → 3]-d-GalNAc, at 0.1 μM, corresponding to 38.3 ng mL− 1. Also shown were the calibration plots of GalNAc (Fig. 1.4A) and Gal (Fig. 1.4B), with 2.7 μM and 1 μM detection limits respectively. The sensitivity trend was found to be consistent with the square-wave voltammetric stripping analysis (Fig. 1.3).

1.3 Gold nanoparticles Gold nanoparticles (AuNPs) have attracted many electrochemists due to their large surface area to volume ratio, better electrical properties, higher stability, low particle size, recyclability in redox processes, and higher surface activity and properties [7,42–44]. These properties had made AuNPs one of the active nanomaterials to use as a functional material to detect various biological molecules. Gold nanoparticles can afford the theory of miniaturization of nanoscale sensors [26]. Since a few years, this ability of the sensors to integrate with nanomaterial devices shows a way to the possibility of lab-on-a-chip technology to detect the multiple analytes simultaneously [45]. Kawde and Jang were responsible for developing polymeric beads consisting of a large number of nanoparticles for the amplification of electrical transduction of DNA [46]. The higher amplification and highly sensitive electrochemical stripping detection of the multiple AuNPs tracers were obtained by virtue of the combined use of c­ arrier bead. Also by incorporating catalytic enlargement of the multiple gold particles, higher sensitivity was achieved (in addition to the carrier bead amplifying units and the ultrasensitive electrochemical stripping detection). Linking of the ~ 0.6 μm polystyrene spheres to ~ 0.8 μm magnetic beads indicated the duplex formation of the same due to the structural and morphological understanding of the gold-loaded polymeric beads. The time for gold loading was set at 15 min loading time, after optimization (for 1 × 1011 gold particles solution). The response of this new protocol on chronopotentiometric stripping hybridization, in lower target concentration, exhibited unbelievably larger gold signal relatively with respect to the traditional assay as reported [47]. However, no response was observed for a 1000-fold excess of noncomplementary DNA. A nonlinear peak area increment with the increasing target concentration was reported when the concentration effect in the ultralow DNA concentration was in the range of 100–500 ng mL− 1 [47–49]. The limit of detection was calculated and found to be 40 pg mL− 1 (6 pM) on the S/N = 3 for the response of 100 pg mL− 1 target DNA. This was much lower than the conventional single-particle stripping hybridization assay detection limit of 100 ng mL− 1 [47,50,51]. Even after repeating six consecutive measurements of the 100 ng mL− 1 targeted DNA, an excellent reproducibility was achieved. Extraordinary performance in the ultralow detection of Hg2 + and Cu2 + with high sensitivity was studied on Graphene quantum dots (GQD) functionalized gold nanoparticles (AuNPs) [52]. This was done using anodic stripping voltammetry by drop-casting of the GQD-AuNPs onto a polished glassy carbon electrode and the square wave voltammogram was recorded. An electrochemical ­immunoassay for

Functionalized nanomaterial-based electrochemical sensors

11

carcinoembryonic antigen was also studied by the use of a large surface area of gold nanoparticles. For this, the 3D-AuNPs-Graphene composite was also applied, which captured more primary antibodies at the same time and thus improving the rate of electronic transmission [53].

1.4 Carbon-based materials Different varieties of carbon-based nanomaterials like carbon nanomaterials, nanodiamonds, carbon nanofibers, nano-onions, carbon nanorings, fullerenes, graphene [54,55], and carbon nanotubes [56–61] are becoming the center of attraction to the scientists to pursue research in analytical applications such as electrochemical sensors. These carbon-based nanostructures exhibit specific structures, properties, and a wide range of applications [62–68]. The excellent electrical conductivity of fullerenes and carbon nanotubes is due to the layered sp2-bonded carbon atoms which enhance the charge transferability when in contact with electron donor groups [69].

1.5 Multiwalled nanotubes Multiwalled nanotubes (MWNTs) are a subclass of carbon nanotubes, which are new types of carbon materials formed from the folding of graphene layers into carbon cylinders [70,71]. Their special geometry, unique electronic, mechanical, chemical, and thermal properties made them highly attractive for electrochemical applications [72]. Wang et  al. had developed a novel biosensor for glucose detection-based MWNTs [73]. The MWNT-based enzyme electrode was designed by growing the MWNTs on Si substrate, then followed by evaporating on the top surface of the MWNTs a thin gold film. Later, the substrate was completely removed by etching with a mixture of HNO3 and HF. This provides an amble surface for the glucose oxidase to attach to, hence providing extra sensitivity. The glucose oxidase enzymes mediate the direct electron transfer to the gold transducer and produce the response current. Detail of the chemical reaction is shown below [74]: Glucose + O2 → gluconic acid + H 2 O2

(1.1)

H 2 O2 → 2H + + O2 + 2e −

(1.2)

Amperometry response of MWNT-based biosensor to glucose together with glassy carbon biosensor shows that MWNT-based biosensor exhibits a much stronger response to glucose than glassy carbon biosensor. More interestingly is at a fixed potential of + 0.45 V vs Ag/AgCl, no response was observed with glassy carbon biosensor, whereas MWNT-based biosensor gave a good signal. This further buttresses the higher sensitivity of the MWNT-based biosensor, a property acquired

12

Functionalized Nanomaterial-Based Electrochemical Sensors

due to the nanomaterials that permit the immobilization of more glucose oxidase enzymes [75]. In terms of stability of the biosensors, MWNT-based retained 86.7% of its initial activity after storing in a buffer solution at 4°C for 4 months; however, 37.2% initial activity was retained for glassy carbon biosensor under the same conditions. Multiwalled carbon nanotubes hybrid in conjugation with other electrochemically active materials such as graphene oxide, metal nanoparticles, etc. have been utilized in several electrochemical discoveries ranging from biological to environmental applications [76].

1.6 Graphene Graphene is one of the popular carbon materials that extends the greater anticipations for the future of analytical and electrochemistry [77,78]. Graphene is a one-atom-thick sheet of sp2 hybridized carbon atom composed of 6 membered rings exhibiting a larger surface area, high mechanical strength, high elasticity, and high thermal conductivity than that of single-walled carbon nanotubes [79]. Graphene can be functionalized with carbon nanotubes to fabricate high-performance transparent electrodes, whose resulting features are comparable with indium tin oxide [80]. Recently researchers had developed aptasensor by functionalizing the aptamers with graphene and these sensors are considered to be the next-generation high-­ performance sensors. In these sensors, the graphene naturally adsorbs the unfolded aptamer and desorbs the folded aptamer; this phenomenon of adsorption and desorption is due to the π-π stacking interaction between the purine and pyrimidine bases and the graphene planes [81,82]. The process of graphene functionalization with aptamers can be achieved by a covalent and noncovalent approach. The covalent approach often relies on the oxidation or the reduction of graphene oxide that contains carbonyl and carboxyl functional groups without a preoxidation step and with less impact on the electronic properties [83,84]. Sometimes, graphene can arbitrate the electron transfer due to the presence of high-density edge-plane-like defects present within its structure. Aptamers can also be immobilized on the gold electrode to adsorb graphene nanosheets in the absence of a target which in turn accelerates the electron transfer ratio between the electroactive species and the electrode surface due to the strong π-π interaction. But, in the presence of a target, the binding reaction inhibits the adsorption of graphene and blocks the electron transfer [62]. Wang et al. have taken the advantage of ultrafast electron transfer ratio of graphene and fabricated a label-free electrochemical aptasensor [85]. Loo et al. used graphene oxide nanoplatelets as electroactive labels to detect thrombin [86]. Tertis et al. constructed an immune-sensor to determine acetaminophen in synthetic and real samples by functionalizing the graphite-based screen-printed electrode with graphene oxide which is prefunctionalized with N-hydroxysuccinimide in the presence of 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride [87].

Functionalized nanomaterial-based electrochemical sensors

13

1.7 Carbon nanoparticle-based electrochemical sensor Bidkorbeh et al. constructed a sensitive and selective electrochemical sensor via the drop-casting of a suspension of carbon nanoparticles on the surface of the glassy carbon electrode [88]. The fabricated sensor was used to determine the acetaminophen and tramadol simultaneously in pharmaceuticals and human plasma. The cyclic and differential pulse voltammetric studies of acetaminophen and tramadol were carried out at the modified and bare glassy carbon electrode to study their electrochemical behavior. It showed that carbon nanoparticles enhanced the electroactive surface area and caused a remarkable increase in the peak current due to a thin layer model-based diffusion within a porous layer. This thin layer of the modifier exhibited a catalytic effect and enhanced the rate of the electron transfer process [88]. This method resulted in a new, sensitive, and selective electrochemical sensor utilizing the unique properties of carbon nanoparticles like electrocatalytic, high specific surface area, and adsorptive properties. The fabricated carbon nanoparticles modified glassy carbon electrode showed excellent catalytic effects toward the electro-­oxidation of acetaminophen and tramadol by enhancing the oxidation peak currents and lowering the oxidation overpotential.

1.8 Magnetic nanoparticles Nowadays, magnetic nanoparticles are gaining popularity due to their nanosize, magnetic properties, and economic production [89,90]. It was proved that magnetic nanoparticles with 10–20 nm size exhibit larger surface area, high mass transfer capacity, and demonstrate an excellent supermagnetism and results in faster response [91]. Therefore, magnetic nanoparticles can be incorporated into the transducer materials by dispersion and enhance their attraction by an external magnetic field onto the active detection surface of the biosensor. Further, biomolecules like antibodies, oligonucleotides, and enzymes are immobilized on the magnetic nanoparticles to improve the efficiency of biosensors [91,92]. The sensitivity and selectivity of magnetic nanoparticle functionalized biosensors strongly depend upon their dimensions (10–20 nm size gives excellent results); therefore, extra care should be taken during their preparation. When magnetic nanoparticles are in contact with the electrode surface, then it transfers a redox-active species to the electrode surface and forms a thin film on the electrode surface; this improves the sensitivity of electrochemical devices by amplifying the electrochemical signal [91]. The investigation of nanoparticle functionalized biosensors can be performed by potentiometry [93–96], amperometry [97], electrochemiluminescence [98], electrochemical impedance spectroscopy [99], and voltammetry [100–106]. Protein G functionalized magnetic nanoparticle-based label-free electrochemical immunosensor was reported by Hosu et al. [107] to detect acetaminophen using a carbon-based screen-printed electrode as an immobilization platform. The performances of the optimized immunoassay were tested using two pharmaceutical products containing acetaminophen with excellent recoveries [107]. Table  1.1 shows the magnetic nanoparticle-based biosensors reported by various researchers.

14

Functionalized Nanomaterial-Based Electrochemical Sensors

Table 1.1  The magnetic nanoparticle-based biosensors reported by various researchers. Instrument used

Type of magnetic nanoparticles used

Voltammetry

Au-Fe3O4

Voltammetry Potentiometry Amperometry Amperometry Electrochemical impedance spectroscopy Electrochemical impedance spectroscopy

Fe3O4@Au-MWNT chitosan Core-shell-Fe3O4 Core-shell Au-Fe3O4@SiO2 Fe3O4@SiO2MWCNT Fe3O4-COOH/Magnetic nanoparticles Fe@Au nanoparticle-2aminoethanethiol-graphene

Target analyte

References

Organochloride pesticides Streptomycin Glucose Glucose Glucose Ochratoxin A

[100]

DNA

[111]

[108] [109] [97] [110] [99]

1.9 Zinc oxide nanotubes Recently it was found that ZnO nanotubes (ZnONTs) have numerous applications in electrochemical biosensors. The related properties responsible included its biocompatibility, nontoxicity, fast electron-transfer rate, and easy application [112,113]. ZnONTs have also been reported for application in glucose detection [18]. Based on the same principle of glucose oxidation by glucose oxidase enzyme, the above work was designed. After the optimization of the experimental parameters such as voltage, pH, and temperature, it was observed that voltage = 0.8 V, pH = 7, and temperature = 50°C were the suited conditions before the amperometric detection of glucose. However, the temperature was maintained at 25°C throughout the analysis (to avoid the evaporation of solvent). A biosensor based on ZnONT to respond faster and sensitively to glucose in PB solution was reported. A straight line and the linear response range was observed from 50 μM to 12 mM from a calibration plot for different glucose concentrations. The sensitivity was found to be 21.7 μA/mM cm2 and LOD determined was 1 μM (S/N = 3). The sensitivity comparison of ZnONT with ZnO nanorods (ZnONR) and Au film was studied. In all cases, ZnONT stands out to be the best out of the lot and this was attributed to the structure of ZnONT which provided a higher electrode surface area for glucose oxidase immobilization. The effect of interference by some electroactive species such as ascorbic acid, l-Cysteine, and urea was performed and little or no response was recorded for both l-Cysteine and urea while ascorbic acid showed a current increment of 9.0% which is still insignificant considering its concentration in physiological condition [114], thus providing negligible effect for glucose determination in the serum sample. ZnO also found application in ethanol gas sensing. A recent study showed that the zinc oxide (ZnO) nanorods synthesized via a low-temperature hydrothermal process were utilized to build an ethanol gas sensor at different operating temperatures by measuring the output voltage signal and has demonstrated high, reversible,

Functionalized nanomaterial-based electrochemical sensors

15

and fast response to ethanol [115]. To improve the sensing performance, the ZnO was later grown 90 degrees to the axis of tin oxide (SnO2) nanowires, which were synthesized by thermal evaporation, to form a hierarchical nanostructure [116]. It was discovered that these hierarchical nanostructures enriched the response of ethanol gas and its selectivity for interfering gases such as NH3, CO, H2, CO2, and LPG. Metal dopants like Platinum and palladium in ZnO nanoarrays were also studied as self-powered active ethanol gas sensor applications at room temperature by uniformly distributing the metal nanoparticles on the surface of the ZnO nanowire [117,118]. The above study was credited to the catalytic effect of the metal nanoparticles, the Schottky barrier at the metal/ZnO interface, and the piezotronics effect of the ZnO nanowires. Single crystalline Zinc sulfide nanowires grown by thermal evaporation have also shown high sensitivity, fast response and recovery times, and high selectivity toward the detection of acetone and ethanol even at low concentration levels of 500 ppb [119].

1.10 Nickel oxide nanoparticles and carbon black A glassy carbon electrode modified with Nickel oxide nanoparticles (NiONPs) and carbon black was reported to be a simple and highly selective electrode for combined determination of paracetamol (PCT) and codeine (COD) [120]. The NiONPs are important nanomaterials due to their specific chemical, surface, and microstructural properties [121]. NiONPs were electrodeposited on a carbon black-di-hexadecyl phosphate (CB-DHP) dispersed glassy carbon electrode, forming the NiONPs-CBDHP/GCE electrode as the indicator electrode. The NiONPs-CB-DHP/GCE was electrochemically characterized using cyclic voltammetry and optimization of the electrochemical behavior of target analytes was carried out using cyclic voltammetry and square wave voltammetry. The cyclic voltammograms for NiONPs-CB-DHP/ GCE presented in Fig. 1.5 show a reversible process after different scan rates, which ­confirmed the formation of NiONPs on the electrode surface. The reversible process is based on the equation below: Ni ( OH )2 + OH − ↔ NiO ( OH ) + H 2 O + e −

(1.3)

The electrochemical behavior of PCT and COD shows a synergic effect upon the incorporation of NiONPs to the CB-DHP/GCE electrode for both PCT and COD due to the increase in the analytical signal. The increased signal was attributed to the chemical interaction between the NiONPs and the OH groups present in the drug structures [122]. Effect of pH for the detection of the PCT and COD using the NiONPs-CBDHP/GCE electrode was investigated by varying pH between the range of 2.0–7.0 and it was observed that for PCT increase in pH resulted in a negative shift in potential for the anodic and cathodic peak current. However, COD showed the largest current signal at a pH of 3, and thus BR buffer solution at pH 3.0 was used for further analysis. Electrochemical behavior to various supporting electrolytes

16

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 1.5  Cyclic voltammograms obtained for the NiONPs-CB-DHP/GCE in 0.1 mol L− 1 NaOH solution at different scan rates: (1–10): 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 mV s− 1. Inset: log ja vs log v. Courtesy: P.B. Deroco, F.C. Vicentini, O. Fatibello‐Filho, An electrochemical sensor for the simultaneous determination of paracetamol and codeine using a glassy carbon electrode modified with nickel oxide nanoparticles and carbon black, Electroanalysis 27 (2015) 2214–2220.

was also investigated using 0.04 mol L− 1 BR buffer (pH 3.0), 0.1 mol L− 1 phosphate ­buffer (pH 3.0), and 0.1 mol L− 1 KNO3 solution (pH 3.0, adjusted with a 0.5 mol L− 1 HNO3 solution). Best analytical signals were obtained with a BR buffer solution. The response of PCT and COD in the presence of each other was then carried out after the optimization using square wave voltammetry, in the first case keeping a constant COD concentration and varying the concentration of PCT and in the second case, the vice versa. Fig. 1.6A and B shows that both variables have increase response with increasing concentration while the response of the fixed analyte remains practically constant and it was confirmed that with both PCT and COD in the same solution, they do not interfere with each other. Then, the authors carried out the simultaneous addition of the different concentrations of the analytes and the limit of detection for both analytes was determined to be 012 μmol L− 1 for PCT and 0.48 μmol L− 1 for COD (S/N = 3) (see Fig. 1.7). The intra-day repeatability after 10 successive measurements and interday repeatability after three consecutive days gave RSD of 3.7% for PCT and 7.8% for COD and 8.8% for both PCT and COD respectively. The interferences effect due to sodium benzoate, silicon dioxide, EDTA, sodium bisulfite, magnesium stearate, starch, and cellulose was evaluated and it was found that there was no significant interference in the simultaneous detection of PCT and COD.

Functionalized nanomaterial-based electrochemical sensors

(a) j (µA cm–2)

j (µA cm–2)

60

40

40 20 0

20

17

2

6

8 4 6 [PCT] (µmol L–1) RSD = 2.1 %

1

0 0.6

0.8 E (V) vs. Ag/AgCl

j (µA cm–2)

30 20

j (µA cm–2)

50 40

1.2

1.0

(b)

30 20 10 0 0

RSD = 3.1 %

6 12 18 24 [COD] (µmol L–1)

5

10 1 0 0.6

0.8 E (V) vs. Ag/AgCl

1.0

1.2

Fig. 1.6  Square-wave voltammograms obtained using the NiONPs-CB-DHP/GCE for various concentrations of (A) PCT (3.0–8.5 μmol L− 1) at a fixed concentration of COD (5.2 μmol L− 1); (B) COD (2.3–4.9 μmol L− 1) at a fixed concentration of PCT (7.2 μmol L− 1). Courtesy: P.B. Deroco, F.C. Vicentini, O. Fatibello‐Filho, An electrochemical sensor for the simultaneous determination of paracetamol and codeine using a glassy carbon electrode modified with nickel oxide nanoparticles and carbon black, Electroanalysis 27 (2015) 2214–2220.

The results achieved were thus compared with some previously reported studies and found that the developed biosensor, at present, was found to be much superior to the first three reported results. The effectiveness of the electrode to real sample analysis by employing two tablets with the known amount (from HPLC analysis) of PCT and COD for electrochemical analysis. The result obtained by the square wave voltammogram was very much comparable to the chromatographic results. The more detailed explanation and the recent development of the nanomaterials and the functionalized nanomaterials-based sensors were reported elsewhere [123–125].

18

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 1.7  Square wave voltammograms obtained using the NiONPs-CB-DHP/GCE for various concentrations of PCT and COD (1–10): from 3.0 to 47.8 μmol L− 1 for PCT and from 0.83 to 38.3 μmol L− 1 for COD. Courtesy: P.B. Deroco, F.C. Vicentini, O. Fatibello‐Filho, An electrochemical sensor for the simultaneous determination of paracetamol and codeine using a glassy carbon electrode modified with nickel oxide nanoparticles and carbon black, Electroanalysis 27 (2015) 2214–2220.

1.11 Conclusion The applications of nanomaterials in electrochemical sensors have been highlighted in this article. Nanomaterials such as gold nanoparticles have been shown to act as a label/tag for the amplified detection of DNA, while the large surface area to volume ratio of carbon nanotubes such as multiwalled nanotubes have been utilized in improving the response for detection of glucose. ZnONTs, another class of nanotubes, have also been reported as an excellent nanomaterial for highly sensitive and selective detection of glucose by immobilizing glucose oxidase. The synergic effect of nickel oxide nanoparticles together with carbon black-di-hexadecyl phosphate has also enhanced significantly the signal responses for simultaneous detection of paracetamol and codeine. There is a lot of other nanomaterials’ application in electrochemical sensors that were not presented; however, it is hoped that the information provided will stimulate researchers into an in-depth study of nanomaterial applications in developing viable electrochemical sensors.

Functionalized nanomaterial-based electrochemical sensors

19

References [1] V.L. Colvin, The potential environmental impact of engineered nanomaterials, Nat. Biotechnol. 21 (2003) 1166–1170. [2] R. Shashanka, D. Chaira, Phase transformation and microstructure study of nano-­ structured austenitic and ferritic stainless steel powders prepared by planetary milling, Powder Technol. 259 (2014) 125–136. [3] R. Shashanka, D. Chaira, Development of nano-structured duplex and ferritic stainless steel by pulverisette planetary milling followed by pressureless sintering, Mater Charact 99 (2015) 220–229. [4] R. Shashanka, D. Chaira, Optimization of milling parameters for the synthesis of ­nano-structured duplex and ferritic stainless steel powders by high energy planetary milling, Powder Technol. 278 (2015) 35–45. [5] K. An, G.A. Somorjai, Size and shape control of metal nanoparticles for reaction selectivity in catalysis, ChemCatChem 4 (2012) 1512–1524. [6] R. Shashanka, Synthesis of nano-structured stainless steel powder by mechanical ­alloying-an overview, Int. J. Sci. Eng. Res. 8 (2017) 588–594. [7] R. Shashanka, Effect of sintering temperature on the pitting corrosion of ball milled duplex stainless steel by using linear sweep voltammetry, Anal. Bioanal. Electrochem. 10 (2018) 349–361. [8] S. Song, Y. Qin, Y. He, Q. Huang, C. Fan, H.-Y. Chen, Functional nanoprobes for ultrasensitive detection of biomolecules, Chem. Soc. Rev. 39 (2010) 4234–4243. [9] R. Mout, D.F. Moyano, S. Rana, V.M. Rotello, Surface functionalization of nanoparticles for nanomedicine, Chem. Soc. Rev. 41 (2012) 2539–2544. [10] B. Pelaz, P. del Pino, P. Maffre, R. Hartmann, M. Gallego, S. Rivera-Fernández, J.M. de la Fuente, G.U. Nienhaus, W.J. Parak, Surface functionalization of nanoparticles with polyethylene glycol: effects on protein adsorption and cellular uptake, ACS Nano 9 (2015) 6996–7008. [11] D. Chen, H. Feng, J. Li, Graphene oxide: preparation, functionalization, and electrochemical applications, Chem. Rev. 112 (2012) 6027–6053. [12] B. Kavosi, R. Hallaj, H. Teymourian, A. Salimi, Au nanoparticles/PAMAM dendrimer functionalized wired ethyleneamine-viologen as highly efficient interface for ultra-­ sensitive α-fetoprotein electrochemical immunosensor, Biosens. Bioelectron. 59 (2014) 389–396. [13] X. Jia, S. Dong, E. Wang, Engineering the bioelectrochemical interface using functional nanomaterials and microchip technique toward sensitive and portable electrochemical biosensors, Biosens. Bioelectron. 76 (2016) 80–90. [14] R. Shashanka, Investigation of optical and thermal properties of CuO and ZnO nanoparticles prepared by Crocus sativus (Saffron) flower extract, J. Iran. Chem. Soc. (2020), https://doi.org/10.1007/s13738-020-02037-3. [15] R. Shashanka, H. Esgin, V.M. Yilmaz, Y. Caglar, Fabrication and characterization of green synthesized ZnO nanoparticle based dye-sensitized solar cell, J. Sci. Adv. Mater. Devices 5 (2020) 185–191. [16] R. Shashanka, Non-lubricated dry sliding wear behavior of spark plasma sintered ­nano-structured stainless steel, J. Mater. Environ. Sci. 10 (2019) 767–777. [17] R. Shashanka, Y. Kamacı, R. Taş, Y. Ceylan, A.S. Bülbül, O. Uzun, A.C. Karaoglanli, Antimicrobial investigation of CuO and ZnO nanoparticles prepared by a rapid combustion method, Phys. Chem. Res. 7 (2019) 799–812.

20

Functionalized Nanomaterial-Based Electrochemical Sensors

[18] T. Kong, Y. Chen, Y. Ye, K. Zhang, Z. Wang, X. Wang, An amperometric glucose biosensor based on the immobilization of glucose oxidase on the ZnO nanotubes, Sensors Actuators B Chem. 138 (2011) 344–350. [19] D.L. Langhus, Analytical Electrochemistry, 2nd Edition (Wang, Joseph), J. Chem. Educ. 78 (2011) 457. [20] F.G. Banica, Chemical Sensors and Biosensors: Fundamentals and Applications, John Wiley & Sons, 2012. [21] N.J. Ronkainen, H.B. Halsall, W.R. Heineman, Electrochemical biosensors, Chem. Soc. Rev. 39 (2010) 1747–1763. [22] D. Zhang, Q. Liu, Biosensors and bioelectronics on smartphone for portable biochemical detection, Biosens. Bioelectron. 75 (2016) 273–284. [23] I. Voiculescu, A.N. Nordin, Acoustic wave based MEMS devices for biosensing applications, Biosens. Bioelectron. 3 (2012) 1–9. [24] J. Cao, T. Sun, K.T.V. Grattan, Gold nanorod-based localized surface plasmon resonance biosensors: a review, Sensors Actuators B Chem. 195 (2014) 332–351. [25] D.C. Ferrier, Micro- and nano-structure based oligonucleotide sensors, Biosens. Bioelectron. 68 (2015) 798–810. [26] G. Maduraiveeran, W. Jin, Nanomaterials based electrochemical sensor and biosensor platforms for environmental applications, Trends Environ. Anal. Chem. 13 (2017) 10–23. [27] L. Rassaei, F. Marken, M. Sillanpää, M. Amiri, C.M. Cirtiu, M. Sillanpää, Nanoparticles in electrochemical sensors for environmental monitoring, Trends Anal. Chem. 30 (2011) 1704–1715. [28] A. Walcarius, Electrocatalysis, sensors and biosensors in analytical chemistry based on ordered mesoporous and macroporous carbon-modified electrodes, Trends Anal. Chem. 38 (2012) 79–97. [29] D.W. Kimmel, G. LeBlanc, M.E. Meschievitz, D.E. Cliffel, Electrochemical sensors and biosensors, Anal. Chem. 84 (2012) 685–707. [30] Y. Wang, A. Hu, Carbon quantum dots: synthesis, properties and applications, J. Mater. Chem. C 2 (2014) 6921–6939. [31] Q. Liang, W. Ma, Y. Shi, Z. Li, X. Yang, Easy synthesis of highly fluorescent carbon quantum dots from gelatin and their luminescent properties and applications, Carbon 60 (2013) 421–428. [32] J.A. Hansen, J. Wang, A.-N. Kawde, Y. Xiang, K.V. Gothelf, G. Collins, Quantum-dot/ aptamer-based ultrasensitive multi-analyte electrochemical biosensor, J. Am. Chem. Soc. 128 (2006) 2228–2229. [33] A.W. Ellington, J.W. Szostak, In vitro selection of RNA molecules that bind specific ligands, Nature 346 (1990) 818–822. [34] K. Ikebukuro, C. Kiyohara, K. Sode, Novel electrochemical sensor system for protein using the aptamers in sandwich manner, Biosens. Bioelectron. 20 (2005) 2168–2172. [35] J. Wang, Nanomaterial-based amplified transduction of biomolecular interactions, Small 1 (2005) 1036–1043. [36] R. Nutiu, Y. Li, Structure-switching signaling aptamers, J. Am. Chem. Soc. 125 (2003) 4771–4778. [37] M. Levy, S.F. Cater, A.D. Ellington, Quantum-dot aptamer beacons for the detection of proteins, ChemBioChem 6 (2005) 2163–2166. [38] A.C. Grimsdale, K. Müllen, The chemistry of organic nanomaterials, Angew. Chem. Int. Ed. 44 (2005) 5592–5629.

Functionalized nanomaterial-based electrochemical sensors

21

[39] Z. Dai, A.-N. Kawde, Y. Xiang, J.T. La Belle, J. Gerlach, V.P. Bhavanandan, L. Joshi, J. Wang, Nanoparticle-based sensing of glycan–lectin interactions, J. Am. Chem. Soc. 128 (2006) 10018–10019. [40] T.A. Taton, G. Lu, C.A. Mirkin, Two-color labeling of oligonucleotide arrays via size-­ selective scattering of nanoparticle probes, J. Am. Chem. Soc. 123 (2001) 5164–5165. [41] M.J. Swamy, D. Gupta, S.K. Mahanta, A. Surolia, Further characterization of the saccharide specificity of peanut (Arachis hypogaea) agglutinin, Carbohydr. Res. 213 (1991) 59–67. [42] X. Zhang, Y. Xu, Y. Yang, X. Jin, S. Ye, S. Zhang, L. Jiang, A new signal-on photoelectrochemical biosensor based on a graphene/quantum-dot nanocomposite amplified by the dual-quenched effect of bipyridinium relay and AuNPs, Chemistry 18 (2012) 16411–16418. [43] M.T. Castañeda, S. Alegret, A. Merkoçi, Electrochemical sensing of DNA using gold nanoparticles, Electroanalysis 19 (2007) 743–753. [44] X. Niu, W. Yang, G. Wang, J. Ren, H. Guo, J. Gao, A novel electrochemical sensor of bisphenol A based on stacked graphene nanofibers/gold nanoparticles composite modified glassy carbon electrode, Electrochim. Acta 98 (2013) 167–175. [45] B. Wolfrum, E. Katelhon, A. Yakushenko, K.J. Krause, N. Adly, M. Huske, P. Rinklin, Nanoscale electrochemical sensor arrays: redox cycling amplification in dual-electrode systems, Acc. Chem. Res. 49 (2016) 2031–2040. [46] A.-N. Kawde, J. Wang, Amplified electrical transduction of DNA hybridization based on polymeric beads loaded with multiple gold nanoparticle tags, Electroanalysis 16 (2004) 101–107. [47] J. Wang, D. Xu, A.-N. Kawde, R. Polsky, Metal nanoparticle-based electrochemical stripping potentiometric detection of DNA hybridization, Anal. Chem. 73 (2001) 5576–5581. [48] N.T.K. Thanh, Z. Rosenzweig, Development of an aggregation-based immunoassay for anti-protein a using gold nanoparticles, Anal. Chem. 74 (2002) 1624–1628. [49] E.T. Kisak, M.T. Kennedy, D. Trommeshauser, J.A. Zasadzinski, Self-limiting aggregation by controlled ligand−receptor stoichiometry, Langmuir 16 (2000) 2825–2831. [50] T.A. Taton, C.A. Mirkin, R.L. Letsinger, Scanometric DNA array detection with nanoparticle probes, Science 289 (2000) 1757–1760. [51] F. Patolsky, K.T. Ranjit, A. Lichtenstein, I. Willner, Dendritic amplification of DNA analysis by oligonucleotide-functionalized Au-nanoparticles, Chem. Commun. (2000) 1025–1026. [52] S.L. Ting, S.J. Ee, A. Ananthanarayanana, K.C. Leong, P. Chen, Graphene quantum dots functionalized gold nanoparticles for sensitive electrochemical detection of heavy metal ions, Electrochim. Acta 172 (2015) 7–11. [53] G. Sun, J. Lu, S. Ge, X. Song, J. Yu, M. Yan, J. Huang, Ultrasensitive electrochemical immunoassay for carcinoembryonic antigen based on three-dimensional macroporous gold nanoparticles/graphene composite platform and multienzyme functionalized nanoporous silver label, Anal. Chim. Acta 775 (2013) 85–92. [54] J.G. Manjunatha, M. Deraman, Graphene paste electrode modified with sodium dodecyl sulfate surfactant for the determination of dopamine, ascorbic acid and uric acid, Anal. Bioanal. Electrochem. 9 (2017) 198–213. [55] J.G. Manjunatha, Electrochemical polymerised graphene paste electrode and application to catechol sensing, Open Chem. Eng. J. 13 (2019) 81–87. [56] N.S. Prinith, J.G. Manjunatha, Polymethionine modified carbon nanotube sensor for sensitive and selective determination of L-tryptophan, J. Electrochem. Sci. Eng. 10 (2020) 305–315.

22

Functionalized Nanomaterial-Based Electrochemical Sensors

[57] M.M. Charithra, J.G. Manjunatha, Enhanced voltammetric detection of paracetamol by using carbon nanotube modified electrode as an electrochemical sensor, J. Electrochem. Sci. Eng. 10 (2020) 29–40. [58] J.G. Manjunatha, Surfactant modified carbon nanotube paste electrode for the sensitive determination of mitoxantrone anticancer drug, J. Electrochem. Sci. Eng. 7 (2017) 39–49. [59] J.G. Manjunatha, M. Deraman, N.H. Basri, N.S. Mohd Nor, I.A. Talib, N. Ataollahi, Sodium dodecyl sulfate modified carbon nanotubes paste electrode as a novel sensor for the simultaneous determination of dopamine, ascorbic acid, and uric acid, C. R. Chim. 17 (2014) 465–476. [60] J.G. Manjunatha, M. Deraman, N.H. Basri, I.A. Talib, Fabrication of poly (Solid Red A) modified carbon nano tube paste electrode and its application for simultaneous determination of epinephrine, uric acid and ascorbic acid, Arab. J. Chem. 11 (2018) 149–158. [61] G. Tigari, J.G. Manjunatha, C. Raril, N. Hareesha, Determination of riboflavin at carbon nanotube paste electrodes modified with an anionic surfactant, ChemistrySelect 4 (2019) 2168–2173. [62] R. Săndulescu, M. Tertiş, C. Cristea, E. Bodoki, Biosensors—micro and nanoscale applications, in: New Materials for the Construction of Electrochemical Biosensors, 2015, https://doi.org/10.5772/60510 (Chapter 1). [63] N. Hareesha, J.G. Manjunatha, C. Raril, G. Tigari, Design of novel surfactant modified carbon nanotube paste electrochemical sensor for the sensitive investigation of tyrosine as a pharmaceutical drug, Adv. Pharm. Bull. 9 (2019) 132–137. [64] N. Hareesha, J.G. Manjunatha, A simple and low-cost poly (DL-phenylalanine) modified carbon sensor for the improved electrochemical analysis of Riboflavin, J. Sci. Adv. Mater. Devices 5 (2020) 502–511. [65] P.A. Pushpanjali, J.G. Manjunatha, Electroanalysis of sodium alizarin sulfonate at surfactant modified carbon nanotube paste electrode: a cyclic voltammetric study, J. Mater. Environ. Sci. 10 (2019) 939–947. [66] B.M. Amrutha, J.G. Manjunatha, A.S. Bhatt, C. Raril, P.A. Pushpanjali, Electrochemical sensor for the determination of alizarin red-S at non-ionic surfactant modified carbon nanotube paste electrode, Phys. Chem. Res. 7 (2019) 523–533. [67] P.A. Pushpanjali, J.G. Manjunatha, A sensitive novel approach towards the detection of 8-hydroxyquinoline at anionic surfactant modified carbon nanotube based biosensor: a voltammetric study, Phys. Chem. Res. 7 (2019) 813–822. [68] G. Tigari, J.G. Manjunatha, Electrochemical preparation of poly (arginine)-modified carbon nanotube paste electrode and its application for the determination of pyridoxine in the presence of riboflavin: an electroanalytical approach, J. Anal. Test. 3 (2019) 331–340. [69] M. Wooten, W. Gorski, Facilitation of NADH electrooxidation at treated carbon nanotubes, Anal. Chem. 82 (2010) 1299–1304. [70] V. Mani, B. Devadas, S.-M. Chen, Direct electrochemistry of glucose oxidase at electrochemically reduced graphene oxide-multiwalled carbon nanotubes hybrid material modified electrode for glucose biosensor, Biosens. Bioelectron. 41 (2013) 309–315. [71] C. Han, A. Doepke, W. Cho, V. Likodimos, A.A. de la Cruz, T. Back, W.R. Heineman, H.B. Halsall, V.N. Shanov, M.J. Schulz, P. Falaras, D.D. Dionysiou, A multiwalled-­ carbon-nanotube-based biosensor for monitoring microcystin-LR in sources of drinking water supplies, Adv. Funct. Mater. 23 (2013) 1807–1816. [72] J. Kong, N.R. Franklin, C. Zhou, M.G. Chapline, S. Peng, K. Cho, H. Dai, Nanotube molecular wires as chemical sensors, Science 287 (2000) 622–625. [73] S.G. Wang, Q. Zhang, R. Wang, S.F. Yoon, A novel multi-walled carbon nanotube-based biosensor for glucose detection, Biochem. Biophys. Res. Commun. 311 (2003) 572–576.

Functionalized nanomaterial-based electrochemical sensors

23

[74] W. Schuhmann, in: M. Lambrechts, W. Sansen (Eds.), Biosensors: Microelectrochemical Devices, Institute of Physics Publishing, Bristol, 1992, p. 304. [75] S. Creager, Electrochemical Sensors in Bioanalysis By Raluca-Ioana Stefan and Jacobus Frederick Van Staden (University of Pretoria, Pretoria, South Africa) and Hassan Y. Aboul-Enein (King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia). Marcel Dekker Inc: New York and Basel. 2001. xxii + 288 pp. $150.00. ISBN 0-8247-0662-5, J. Am. Chem. Soc. 124 (2002) 511–512. [76] S. Creager, Electrochemical Sensors in Bioanalysis by Raluca-Ioana Stefan and Jacobus Frederick Van Staden, University of Pretoria, Pretoria, 2001, p. 288. [77] J.G. Manjunatha, Poly (adenine) modified graphene-based voltammetric sensor for the electrochemical determination of catechol, hydroquinone and resorcinol, Open Chem. Eng. J. 14 (2020) 52–62. [78] J.G. Manjunatha, A surfactant enhanced graphene paste electrode as an effective electrochemical sensor for the sensitive and simultaneous determination of catechol and resorcinol, Chem. Data Collect. 25 (2020) 100331. [79] M. Pumera, A. Ambrosi, A. Bonanni, E.L.K. Chng, H.L. Poh, Graphene for electrochemical sensing and biosensing, TrAC Trends Anal. Chem. 29 (9) (2010) 954–965. [80] X. Guoqing, W. Hwang, N. Kim, S.M. Cho, H. Chae, A graphene sheet exfoliated with microwave irradiation and interlinked by carbon nanotubes for high-performance transparent flexible electrodes, Nanotechnology 21 (2010) 405201–405207. [81] Y.X. Liu, X.C. Dong, P. Chen, Biological and chemical sensors based on graphene materials, Chem. Soc. Rev. 41 (6) (2012) 2283–2307. [82] J.W. Park, S.J. Lee, E.J. Choi, J. Kim, J.Y. Song, M.B. Gu, An ultra-sensitive detection of a whole virus using dual aptamers developed by immobilization-free screening, Biosens. Bioelectron. 51 (2014) 324–329. [83] V. Biju, Chemical modifications and bioconjugate reactions of nanomaterials for sensing, imaging, drug delivery and therapy, Chem. Soc. Rev. 43 (2014) 744–764. [84] E. Bekyarova, M.E. Itkis, P. Ramesh, C. Berger, M. Sprinkle, W.A. de Heer, R.C. Haddon, Chemical modification of epitaxial graphene: Spontaneous grafting of aryl groups, J. Am. Chem. Soc. 131 (2009) 1336–1337. [85] L. Wang, M. Xu, L. Han, M. Zhou, C.Z. Zhu, S.J. Dong, Graphene enhanced electron transfer at aptamer modified electrode and its application in biosensing, Anal. Chem. 84 (2012) 7301–7307. [86] A.H. Loo, A. Bonanni, M. Pumera, Thrombin aptasensing with inherently electroactive graphene oxide nanoplatelets as labels, Nanoscale 5 (2013) 4758–4762. [87] M. Tertis, O. Hosu, L. Fritea, C. Farcau, A. Cernat, R. Sandulescu, C. Cristea, A novel label-free immunosensor based on activated graphene oxide for acetaminophen detection, Electroanalysis 27 (2015) 638–647. [88] F. Ghorbani-Bidkorbeh, S. Shahrokhian, A. Mohammadi, R. Dinarvand, Simultaneous voltammetric determination of tramadol and acetaminophen using carbon nanoparticles modified glassy carbon electrode, Electrochim. Acta 55 (2010) 2752–2759. [89] R. Shashanka, K.B. Ceylan, The activation energy and antibacterial investigation of spherical Fe3O4 nanoparticles prepared by Crocus sativus (Saffron) flowers, Biointerface Res. Appl. Chem. 10 (2020) 5951–5959. [90] R. Shashanka, A.C. Karaoglanli, Y. Ceylan, O. Uzun, A fast and robust approach for the green synthesis of spherical magnetite (Fe3O4) nanoparticles by Tilia tomentosa (Ihlamur) leaves and its antibacterial studies, Pharm. Sci. 26 (2020) 175–183. [91] T.A.P. Rocha-Santos, Sensors and biosensors based on magnetic nanoparticles, TrAC Trends Anal. Chem. 62 (2014) 28–36.

24

Functionalized Nanomaterial-Based Electrochemical Sensors

[92] J.F. Rusling, G. Sotzing, F. Papadimitrakopoulos, Designing nanomaterials-enhanced electrochemical immunosensors for cancer biomarker proteins, Bioelectrochemistry 76 (2009) 189–194. [93] R. Shashanka, B.E. Kumara Swamy, Simultaneous electro‑generation and electro-­ deposition of copper oxide nanoparticles on glassy carbon electrode and its sensor application, SN Appl. Sci. 2 (2020) 956. [94] R. Shashanka, B.E.K. Swamy, Biosynthesis of silver nanoparticles using leaves of Acacia melanoxylon and its application as dopamine and hydrogen peroxide sensors, Phys. Chem. Res. 8 (2020) 1–18. [95] R. Shashanka, D. Chaira, B.E.K. Swamy, Electrochemical investigation of duplex stainless steel at carbon paste electrode and its application to the detection of dopamine, ascorbic and uric acid, Int. J. Sci. Eng. Res. 6 (2015) 1863–1871. [96] R. Shashanka, B.E.K. Swamy, S. Reddy, D. Chaira, Synthesis of silver nanoparticles and their applications, Anal. Bioanal. Electrochem. 5 (2013) 455–466. [97] X. Chen, J. Zhu, Z. Chen, C. Xu, Y. Wang, C. Yao, A novel bienzyme glucose biosensor based on three layers Au-Fe3O4@SiO2 magnetic nanocomposite, Sensors Actuators B Chem. 159 (2011) 220–228. [98] H. Zhou, N. Gan, T. Li, Y. Cao, S. Zeng, L. Zheng, Z. Guo, The sandwich-type electroluminescence immunosensor for α-fetoprotein based on enrichment by Fe3O4-Au magnetic nano probes and signal amplification by CdS-Au composite nanoparticles labeled anti-AFP, Anal. Chim. Acta 746 (2012) 107–113. [99] L.-G. Zamfir, I. Geana, S. Bourigua, L. Rotariu, C. Bala, A. Errachid, N. Jaffrezic-Renault, Highly sensitive label-free immunosensor for ochratoxin A based on functionalized magnetic nanoparticles and EIS/SPR detection, Sensors Actuators B Chem. 159 (2011) 178–184. [100] N. Gan, X. Yang, D. Xie, Y. Wu, W. Wen, A disposable organophosphorus pesticides enzyme biosensor based on magnetic composite nano-particles modified screen printed carbon electrode, Sensors 10 (2010) 625–638. [101] R. Shashanka, D. Chaira, B.E.K. Swamy, Fabrication of yttria dispersed duplex stainless steel electrode to determine dopamine, ascorbic and uric acid electrochemically by using cyclic voltammetry, Int. J. Sci. Eng. Res. 7 (2016) 1275–1285. [102] R. Shashanka, D. Chaira, B.E.K. Swamy, Electrocatalytic response of duplex and yittria dispersed duplex stainless steel modified carbon paste electrode in detecting folic acid using cyclic voltammetry, Int. J. Electrochem. Sci. 10 (2015) 5586–5598. [103] S. Reddy, B.E.K. Swamy, S. Aruna, M. Kumar, R. Shashanka, H. Jayadevappa, Preparation of NiO/ZnO hybrid nanoparticles for electrochemical sensing of dopamine and uric acid, Chem. Sens. 2 (2012) 1–7. [104] P.A. Pushpanjali, G. Jamballi, Manjunatha, Development of polymer modified electrochemical sensor for the determination of alizarin carmine in the presence of tartrazine, Electroanalysis 32 (2020) 1–8. [105] N.S. Prinith, J.G. Manjunatha, C. Raril, Electrocatalytic analysis of dopamine, uric acid and ascorbic acid at poly(adenine) modified carbon nanotube paste electrode: a cyclic voltammetric study, Anal. Bioanal. Electrochem. 11 (2019) 742–756. [106] N. Hareesha, J.G. Manjunatha, Fast and enhanced electrochemical sensing of dopamine at cost-effective poly(DL-phenylalanine) based graphite electrode, J. Electroanal. Chem. 878 (2020) 114533. [107] O. Hosu, M. Tertis, C. Cristea, R. Sandulescu, Protein G magnetic beads based immunosensor for sensitive detection of acetaminophen, Farmacia 63 (2015) 143–146. [108] Y. Hu, Z. Zang, H. Zhang, L. Luo, S. Yao, Selective and sensitive molecularly imprinted sol-gel film-based electrochemical sensor combining mecaptoacetic acid modified PbS

Functionalized nanomaterial-based electrochemical sensors

[109] [110]

[111]

[112]

[113]

[114]

[115]

[116] [117]

[118]

[119]

[120] [121]

[122]

[123] [124] [125]

25

nanoparticles with Fe3O4@Au-multi-walled carbon nanotubes-chitosan, J. Solid State Electrochem. 16 (3) (2012) 857–867. Z. Yang, C. Zhang, J. Zhang, W. Bai, Potentiometric glucose biosensor based core-shell Fe3O4-enzyme-polypyrrole nanoparticles, Biosens. Bioelectron. 51 (2014) 268–273. J. Jia, B. Wang, A. Wu, G. Cheng, Z. Li, S. Dong, A method to construct a third generation horseradish peroxidase biosensor: self-assembling gold nanoparticles to three dimensional sol-gel network, Anal. Chem. 74 (2002) 2217–2223. M.L. Yola, T. Eren, N. Atar, A novel and sensitive electrochemical DNA biosensor based on Fe@Au nanoparticles decorated graphene oxide, Electrochim. Acta 125 (2014) 38–47. G.-E. Chen, S.‐.J. Xu, Z.‐.L. Xu, W.‐.W. Zhu, Q. Wu, W.‐.G. Sun, Preparation and characterization of a novel hydrophilic PVDF/PVA UF membrane modified by carboxylated multiwalled carbon nanotubes, Polym. Eng. Sci. 56 (2016) 955–967. X. Zhu, I. Yuri, X. Gan, I. Suzuki, G. Li, Electrochemical study of the effect of nano-zinc oxide on microperoxidase and its application to more sensitive hydrogen peroxide biosensor preparation, Biosens. Bioelectron. 22 (2007) 1600–1604. Z.W. Zhao, X.J. Chen, B.K. Tay, J.S. Chen, Z.J. Han, K.A. Khor, A novel aerometric biosensor based on ZnO: Co nanoclusters for bio sensing glucose, Biosens. Bioelectron. 23 (2007) 135–139. Z.-X. Zhao, M.-Q. Qiao, F. Yin, B. Shao, B.-Y. Wu, Y.-Y. Wang, X.-S. Wang, X. Qin, S. Li, L. Yu, Q. Chen, Aerometric glucose biosensor based on self-assembly hydrophobin with high efficiency of enzyme utilization, Biosens. Bioelectron. 22 (2007) 3021–3027. L. Wang, Y. Kang, X. Liu, S. Zhang, W. Huang, S. Wang, ZnO nanorod gas sensor for ethanol detection, Sensors Actuators B Chem. 162 (2012) 237–243. N.D. Khoang, D.D. Trung, N.V. Duy, N.D. Hoa, N.V. Hieu, Design of SnO2/ZnO hierarchical nanostructures for enhanced ethanol gas-sensing performance, Sensors Actuators B Chem. 174 (2012) 594–601. Y. Zhao, X. Lai, P. Deng, Y. Nie, Y. Zhang, L. Xing, X. Xue, Pt/ZnO nanoarray nanogenerator as self-powered active gas sensor with linear ethanol sensing at room temperature, Nanotechnology 25 (2014) 115502. Y. Lin, P. Deng, Y. Nie, Y. Hu, L. Xing, Y. Zhang, X. Xue, Room-temperature self-­ powered ethanol sensing of a Pd/ZnO nanoarray nanogenerator driven by human finger movement, Nanoscale 6 (2014) 4604–4610. X. Wang, Z. Xie, H. Huang, Z. Liu, D. Chen, G. Shen, Gas sensors, thermistor and photodetector based on ZnS nanowires, J. Mater. Chem. 22 (2012) 6845–6850. P.B. Deroco, F.C. Vicentini, O. Fatibello‐Filho, An electrochemical sensor for the simultaneous determination of paracetamol and codeine using a glassy carbon electrode modified with nickel oxide nanoparticles and carbon black, Electroanalysis 27 (2015) 2214–2220. H. Beitollahi, H. Karimi-Maleh, H. Khabazzadeh, Nanomolar and selective determination of epinephrine in the presence of norepinephrine using carbon paste electrode modified with carbon nanotubes and novel 2-(4-oxo-3-phenyl-3,4-dihydroquinazolinyl)-N′-­phenyl-hydrazinecarbothioamide, Anal. Chem. 80 (2000) 9848–9851. C.M. Hussain, Handbook of Functionalized Nanomaterials for Industrial Applications, Elsevier, 2020. C.M. Hussain, Handbook of Nanomaterials for Sensing Applications, Elsevier, 2020. C.M. Hussain, Handbook of Manufacturing Applications of Nanomaterials, Elsevier, 2020.

This page intentionally left blank

Recent progress in the graphene functionalized nanomaterial-based electrochemical sensors

2

Rajat Kumar Pandeya, Deepak Kapoorb, Deepak Kumara, Rajiv Tonkb, Shankramma Kalikeric, Srilatha Raod, and Gururaj Kudur Jayaprakashe a School of Pharmaceutical Sciences, Shoolini University, Solan, Himachal Pradesh, India, b Department of Pharmaceutical Chemistry, Delhi Pharmaceutical Sciences Research University, New Delhi, India, cDivision of Nanoscience and Technology, Department of Water and Health (Faculty of Life Sciences), JSS Academy of Higher Education & Research (Deemed to be University), Mysore, Karnataka, India, dDepartment of Chemistry, Nitte Meenakshi Institute of Technology, Bangalore, Karnataka, India, eSchool of Advanced Chemical Sciences, Shoolini University, Solan, Himachal Pradesh, India

2.1 Introduction Early-stage diagnosis is a very vital technique for fighting a fatal disease like Cancer or infections with minimal cost for better treatment outcomes. As per the record of the World Health Organization by 2035 every year, there will be almost 24 million new cancer victims and 14.5 million cancer-related deaths [1]. Diabetes is also increased in people of early ages which leads to most of the chronic diseases and deaths as per WHO in 2016 1.6 million death caused by diabetes. Alzheimer’s disease is among the most deadly diseases which lead to memory loss even patients forget to do simple-­ simple work and eventually they forget to inhale oxygen and leads to death. Similarly, Hb is one of the most important blood components which holds oxygen into the blood but its deficiency leads to anemia and then caused various several chronic disorders. In fact, in case of bacterial infection we use the old culture method which is time consuming and some of the strains cannot detect with that so. For preventing these disorders or reducing the seriousness of these diseases, early screening clinical testing, and evaluation of the therapeutic effects, quantitative detections will play an important role. The biosensor is the most important advancement in the healthcare field for the elimination of emerging health issues like cancer, heart disease, Alzheimer’s disease, diabetes, asthma, etc. [2,3]. A biosensor is the most effective, low-cost, tool that combines with a delicate biological component including enzymes, antibodies, nucleic acid, etc. including physiological detectors for detecting various types of target by interacting with biological elements and analytes according to the change of signal [4,5]. There are lots of different nanomaterials used to conjugates with the biological molecules due to their quantum effects like metallic nanomaterials [6,7], silica nanoparticles (NPs) [8], dendrimers, quantum dots (QDs), polymer NPs, carbon nanotubes Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00005-3 Copyright © 2022 Elsevier Ltd. All rights reserved.

28

Functionalized Nanomaterial-Based Electrochemical Sensors

(CNTs), nanodiamonds (NDs) [9,10], and 2D-nanomaterials [graphene [11,12], hexagonal boron nitride (h-BN) [13], transition metal dichalcogenides (TMDs) [14] such as niobium selenide (NbSe2), molybdenum disulfide (MoS2) [15], and tungsten disulfide (WS2) [16]] are extremely reviewed and have a significant addition to biosensor development [17–19]. Among these nanomaterials, graphene is the most encouraging nanostructured biomaterial. Graphene is formed when the carbon atoms are hybridized along with the SP2 electron orbital [20]. Graphene has a large specific surface area, exceptional electron transport capabilities, electrical conductivity, chemical stability, ease of manipulation, and strong mechanical strength which provided the more distinct site to capture external moieties with high sensitivity. These properties make graphene the most encouraging material for biosensors. So due to these properties graphene is considered the most effective in biosensing of different diseases starting from a simple infection to severe cancers like cold, cough, sinus, UTI, Alzheimer’s diseases to cancer. In detecting every kind of disease, we can use graphene-based biosensors.

2.2 Advantages of graphene-based biosensor 1. Graphene has a large specific surface area. Theoretically, it was reported that for single-layer graphene 2630 m2/g, that helps in the high density of attached recognition components or analyte molecules. 2. Graphene has better electron transport capabilities and electronic properties. Graphene has SP2 hybridized carbon atoms that constitute pie-pie conjugates. Along with these properties, graphene is an excellent candidate in the electrochemical sensing field.

Recent progress in the graphene

29

3. The single-layer graphene has a thickness of 0.335 nm, Due to the strong carbon‑carbon double bond in the atom plane, graphene is much harder than the diamond while the diamond having van der Waals force of attraction for interlayer bonding that makes diamond soft material [21,22]. 4. Ease of functionalization—graphene has a special feature; it can easily be modified with different groups of chemicals and biomolecules. Also in the physiological environment, they have high colloidal stability. It provides high drug loading efficacy and site-specific targeting capability after tuning its band gaps [23]. 5. Graphene molecules are very much resistant to the oxidizing agent and graphene can target the specific analyte due to the ability of chemically selective functionalization. 6. Graphene’s entire surface area is available for foreign molecules making it favorable for nanoparticles in detecting absorbed particles. Graphene has different modes of functionalization that helps in capturing specific molecules. Also unlike other nanomaterials, graphene does not have any heterogeneous materials which make it toxic-free in biosensing [24,25].

2.3 Preparation of graphene-based biosensor Graphene and graphene-based derivatives like GO, rGO, porous reduced graphene oxide, and GNRs can be prepared or synthesized by the different methods that include exfoliation and cleavage of natural graphite, chemical vapor deposition (CVD), PE-CVD, electric arc discharge, micromechanical exfoliation of graphite, epitaxial growth on electrically insulating surfaces, such as SiC, opening CNT, and the solution-based reduction of GO. CVD methods are used to prepare immense-quality graphene nanosheets having large-area single or few layers of high-quality graphene nanosheets. These high-­ quality graphene sheets can obtain mono- or bilayer modified electrical interfaces and this type of electrode is advantageous for plasmonic and G-FETs biosensing [26,27]. Sun et al. prepared the graphene by the CVD method using PMMA deposited on a Cu substrate [28]. Dong et al. used natural flake graphite using 1,3,6,8-pyreneterasulfonic acid and D2O for the synthesis of monolayer graphene [29]. By solution-based exfoliation through weakening, the van der wall forces of graphene layers GO and rGO can be prepared from graphite precursor. Most of the G-biosensors are prepared by this method because this is a much more economical method than others on large scale and having the advantages of the modulation of the morphology and porosity of the nanosheets. For improving the electro-catalytic properties and electrical properties of GO and rGO doped them with nonmetallic elements like nitrogen, sulfur, and boron. For coating the chemically derived graphene material with the electrical and inert surfaces by using different methods like drop-casting, spin-coating, electrostatic interaction between positively charged interfaces and the negatively charged GO/rGO nanosheets, electrophoretic deposition (EPD), and electrochemical reduction of GO. Based on the application, different methods can be used for the preparation of the graphene [30].

2.4 Graphene biosensor for glucose and dopamine Glucose is the most important major component for human health as the level of glucose increased in the blood leads to hyperglycemia and diabetes that leads to premature

30

Functionalized Nanomaterial-Based Electrochemical Sensors

death due to microvascular complications, so monitoring the blood glucose level is important to manage the blood glucose level in the body. Lots of efforts and methods have been put into sensing glucose. Different graphene-based glucose biosensors were developed using immobilizing glucose oxidase onto the surface of graphene. Hung et al. [31] developed glucose biosensing in which they covalently linked immobilize glucose oxidase with the 1-pyrenebutanoic acid succinimidyl ester via amine group of GOx where pyrene end is attached to graphene by p-p stacking interactions. Glucose detection was done by measuring the change of conductance down to 0.1 mM, while the GOx also allowed for the highly specific detection of glucose, based on the integration of electro-catalytic sites for glucose in the form of nanoparticles on the graphene the nonenzymatic sensor of glucose works. These sensors are mostly operated in the alkaline medium and are less specific for glucose. These have many advantages such as better stability than the GOx-based interfaces while increasing the detection limits from micromolar to nanomolar ranges sensitivity improved. On the other hand in the case of the N-doped prGO loaded with Cu NPs (N-prGO-Cu NPs), the electro-catalytical behavior of the CuO/CuOOH couple is mainly related to the improved sensitivity to glucose. Cu(I)-glucose complex is formed when on the Redox peak of the Cu(0)/Cu(I) having glucose that remains unchanged and the peak of the Cu(I)/Cu(II) transition is decreased [32]. Based on the GQDs modification along with the boric acid-substituted bipyridine ligand, a nonenzymatic glucose sensing approach was proposed in which it was used as a fluorescence quencher upon electrostatic interaction with GQDs. By adding the glucose into that system, then the boric acids’ moieties were converted onto the tetrahedral anion glucuronate esters, and then the net charge of the bipyridinium was neutralized that led to the effective diminishing the quenching effect and then the intensity of the GQDs fluorescence was recovered [33]. Dopamine is among the essential catecholamine neurotransmitters that are broadly present in the serum samples between the concentration of 10 nM and 1 nM. Any abnormal level of dopamine leads to different diseases like Huntington’s disease, Parkinson’s disease, schizophrenia with increase in the level of dopamine that leads to an increase in blood pressure and its associated disease; thus more accurate detection with the low cost of dopamine is more significant in clinical diagnostics. Dopamine having an electrochemical activity leads to electrochemical detection more accurately. Where in the extracellular fluids of the central nervous system of the mammal’s dopamine is co-existed with the uric acid (UA), ascorbic acid (AA), and serotonin (ST) at very high concentrations and easily oxidizes at a potential nearly to the dopamine. So because the electrochemical properties of the graphene for the dopamine together lead to the p-p interaction that helped in the development of the dopamine-specific graphene sensor even at the high concentration of uric acid (UA), ascorbic acid (AA), and serotonin (ST). With the help of the electrochemically reduced GO along with the combination of the polyvinylpyrrolidone, extremely low LODs can be achieved that can detect dopamine up to 0.2 nm concentration in the presence of the 1 mM AA [34].

Recent progress in the graphene

31

2.5 DNA-based biosensing In the recent past for the development of DNA-based biosensing, GN and GNO have been used as an exclusive platform that gave DNA adsorption due to the detection of DNA hybridization techniques and fluorescence-quenching properties of GNO. There are different advantages of the electrochemical GN-based DNA sensor such as high sensitivity, high selectivity, rapid, and cost-effective analysis for detecting biomolecules. They are playing a very important role in the field of diagnosis and treatment. Primary focus is on the DNA sensing on the sequence-specific recognization and by various techniques mutation of the ssDNA. Due to the properties of the GN, many researchers showed that the GN-based DNA biosensors exhibit excellent sensitivity and selectivity. Chen et al. [35] developed GN-based field-effect transistors (FETs) based on largearea monolayer GN through the CVD technique for label-free electrical detection of DNA hybridization. They have arranged the buffer concentrations, gate material, and surface condition of the GN and then detected the sensitivity of DNA as low as 10–12 mol L−  1. They reported that it was more sensitive than the existing two-layer GN-based biosensor. Zou et al. [36] prepared the biosensor which chemically reduced GNO (CR-GNO) and also had the capabilities to provide resolved signals for DNA that has four bases that were adenine, guanine, cytosine, and thymine on the GNO electrode, and all were detached efficiently and were able to detect four bases. In ssDNA and dsDNA, all these four bases were detached and detected but these were tough to oxidize than free bases, also simultaneously at physiological pH level electrochemical detection of signal nucleotide polymorphisms. That also detected the SNP site for short oligomers with particular sequences at CR-CNO/GCE without any hybridization and labeling process. This showed that CR-GNO had a potential application for detecting DNA hybridization or DNA damage electrochemically. GN has some unique electrochemical properties like excellent conductivity, large surface area, single-sheet nature, large electron transfer rate reduction potential, etc.; these are exceptionally better than graphite and GCEs. Dan li et al. [37] synthesized an electrode material from GNO on which dsDNA was effectively immobilized, which worked as a sensor for monitoring the environment. From the experiment, it was found that the DNA had an electrochemical activity over the electrode and facilitated the transfer of electrons between DNA and GNO electrode. When in electrolyte solution a standard environmental pollutant or hydroquinone was used, then the electrochemical DNA was decreased on the GNO electrode because of the mixing of hydroquinone with the DNA. Based on these results, they further developed the DNA-immobilized GNO electrode as an electrochemical biosensor for the monitoring of hydroquinone. Tian et al. [38] prepared a method using functionalized GN (FG) and methylene blue (MB) for sequence-specific DNA detection. They recognized that after adding FG into the analytes and MB was used as an electrochemically active DNA intercalator, with

32

Functionalized Nanomaterial-Based Electrochemical Sensors

the sensitivity of 48.15% DNA would be detected that was exceptionally greater than that obtained without FG. From this experiment, it was concluded that the FG played a very important role in the detection of DNA through enhancing the sensitivity with the mixing of MB solution. Their system could detect single base pair mismatch from the probe sequences and the target DNA. Bo et al. [39] showed the fabrication of the DNA biosensor, integrating GN along with polyaniline nanowires layer by layer with improved sensitivity for DNA detection. During the analytical performance of DNA sensor through immobilized probe along with different concentration of target DNA, they showed efficient differential pulse voltammetry (DPV) current responses were exhibited by the GN/PANIw for the complementary DNA sequences. With the logarithmic value of the sequence concentration from 2.12 × 10−  6 to 2.12 × 10−  12 mol L−  1, the peak currents of the ssDNA/PANIw/ GN/GCE were linear. From the experiment, they found that the GN and PANIw could give an efficient environment, and an electrode surface, they can directly transfer the electron and they also reported that the ssDNA/PANIw/GCE having high selectivity and sensitivity for the complementary DNA sequences. Zhu et al. [40], based on the thionine-GN nanocomposite, modified gold electrode and they tried to discriminate between ssDNA and hybridized DNA by applying the electrochemically oxidized GN on DNA. They tried to monitor the hybridization reaction on modified electrodes using DPV analysis with the help of an indicator. At the optimum conditions, they found that the biosensor has a high sensitivity for detecting the complementary oligonucleotide at a wide range (1.0 × 10−  12–1.0 × 10−  7 M) with good linearity (R2 = 0.9976) and a low detection limit of 1.26 × 10−  13 M (S/N = 3). Yang et al. [41] based on RGO and PANI nanocomposite prepared an electrochemical biosensor for detecting the HG2 in an aq solution. From the electrochemical impedance spectroscopy, they figure out that the electrochemical biosensor had excellent sensitivity and selectivity for hg2 from 0.1 to 100 nM concentration along with a low detection limit of 0.035 nM. Kakatkar et al. [42] used the technology of DNA detection based on the CVD GN FET biosensor. From the conductance of the GN transistor presence of the poly-l-­ lysine and DNA was detected. When they exposed the GN channel to the solution that contains poly-l-lysine and DNA, a Dirac voltage was observed. This Dirac voltage was attributed to the bounded and unbounded charged molecules on the GN surface, from which they found the polarization of positive charge toward the poly-l-lysine and polarization of negative charge toward the DNA. Detection limits result for 48.5 kbp DNA is 8 pM and 11 pM for poly-l-lysine. Lin et al. [43] prepared an electrochemical DNA biosensor from which they immobilized the capture DNA on the surface of the GN-modified GCE by pie-pie stacking. For detecting the targeted DNA sequences, gold nanoparticles were modified with the single nucleotide and then co-hybridized on the surface of the GCE. After that in a sandwich assay format targeted DNA sequences and oligonucleotide probes labeled AuNPs were able to hybridize following AuNOs-catalyzed silver deposition. Using the pulse volumetric analysis deposited silver was detected. With the high DNA loading capacity of GN and distinct signal amplification by AuNPs catalyzed silver lining biosensor showed efficient analytical performance along with wide detection linear range

Recent progress in the graphene

33

from 200 to 500 pM and a low detection limit of 12 pM. This DNA biosensor was able to discriminate target complementary sequence from a single base pair mismatch.

2.6 Graphene biosensor for protein biomarkers In tissue or blood, there are specific molecules that are called protein biomarkers; these are very efficient and serious parameters in the prediction diagnosis, and monitoring of different diseases like cancer so measurement of these is very crucial. The utility of these biomarkers is very important in diagnosing diseases that require the ability to measure the femto-to picomolar concentration. For understanding the cellular process and looking for new protein biomarkers, these are very important parameters. For biomarkers detection, the LODs of these are lag behind the requirement for clinical utility and research. For capturing the selective biomarkers analyte graphene-based immunoassay platforms were used in which specific antibodies were immobilized onto graphene which shows an excellent sensitivity. As in the case of folic acid protein, in the solution of folic acid postfunctionalized, rGO modified electrodes immersed and permitted for the improvement of an electrochemical based sensor that detects the folic acid protein along with the LODs of 1 pM [44] and a plasmonic sensor with 5 fM [45] LOD and found that in the serum folic acid protein level increased up to 22 pM in case of metastatic diseases. But human serum is free from folic acid protein so it is observed that if the folic acid protein is detected in the serum of human, it can lead to an early-stage diagnosis of cancer. Kim et al. [46] prepared an rGO-based FET improved with prostate-specific antigena1 antichymotrypsin (PSA-ACT) for detecting the level of PSA. Cosnier and co-workers tried to detect the cholera toxins on graphene-coated gold chips which were altered with pyrenenitrilotriacetic acid and having LOD of 5 pg per mL using an SPR-based readout [47]. Serum lysozyme levels were detected with an LOD of 3.4 nM by Micrococcus also deikticus modified GO-coated SPR interfaces. Lysozyme is mainly found in biological fluid with a concentration range of 27–301 nm in healthy individuals while that is increased in the case of leukemia and renal disease also in the case of different inflammatory diseases. Patients having inflammatory bowel diseases showed a micromolar level of lysozyme [48]. For sensitive detection of Alzheimer’s disease biomarkers with 100 fg per mL, a multifunctional nanoplatform based on magnetic-plasmonic NPs that attached to GO was used. When these biosensors were used, there was a problem of nonspecific interaction between the graphene surface and serum proteins. Different strategies were tried and found out that when rGO was modified with the pyrene-po; polyethylene glycol units showed the best nonfouling interface result [49].

2.7 Hb biosensor Hb is the most vital component of the blood which is responsible for the transportation of oxygen and carbon dioxide in the entire circulating system. When Hb concentration deviates from the required concentration then various disease strat occurring like

34

Functionalized Nanomaterial-Based Electrochemical Sensors

a­ nemia, leukemia, heart diseases, and so on. In the entire world, woman and children are suffering from anemia (when Hb level decreases from the required concentration). So it is most important to determine the concentration of Hb into the blood for clinically significant issues. Xu et al. [50] prepared a chitosan-GN improved electrode for Hb electroanalysis. After analyzing, the Hb at the CS-GN/GCE and CS-GCE using the voltammogram found that CS-GN/GCE had a well-defined redox peak as compared to CS-GCE. The surface-controlled electrochemical process was confirmed after observing the current response of the Hb at CS-GN/GCE that linearly increased from 30 to 150  mV per second. Sun et  al. [51] formed an electrochemical biosensor with the help of the three-­ dimensional GN as the substrate electrode and then immobilized the Hb over the substrate electrode with chitosan film. A pair of well resolved redox peaks were observed on CV due to the electrochemical process which indicates the direct electron transfer of Hb. They calculated the electron-transfer coefficient (α) and the apparent heterogeneous electron-transfer rate constant (ks) was calculated to be 0.426 and 1.864 s−  1, respectively, based on the excellent conductivity and large surface area of 3D-GN. Due to the reduction of the trichloroacetic acid (TCA), these modified electrodes gave effective electrocatalytic activity and also observed the linear response of the catalytic reduction peak to TCA concentration within the range from 0.4 to 26 nM/L with the detection limit of 0.133 mM/L.

2.8 Cholesterol biosensor Cholesterol is one of the major causes of heart disease. An increase in the level of cholesterol in arteries and blood leads to various serious diseases like coronary heart diseases, cerebral thrombosis, and atherosclerosis, and due to which many people died due to heart attacks in India and other countries. So it is most important to determine the level of cholesterol in the blood and arteries. Cao et  al. [52] fabricated an electrochemical biosensor using the platinum‑­ palladium-CS-GN hybrid (PtPd-CS-GN) nanoparticles functionalized GCE with improved sensitivity for detecting the cholesterol. They found that the PtPd-CS-GN nanocomposite helped in the direct electron transfer from the redox enzyme to the electrode surface as well as enhanced the immobilized volume of cholesterol oxidase. They observed that the biosensor showed a wide linear value of responses to cholesterol within the concentration of 2.2 × 10−  6 to 5.2 × 10−  4 M/L and the detection limit was found as 0.75 μM/L (S/N = 3). For the electrode, they reported the response time and the Michaelis-Menten constant was 0.11 mM/L. The biosensor showed very good stability and efficiency and reproducibility. Li et  al. [53] prepared a cholesterol biosensor by immobilizing ChOx on GCE functionalized using the CS-GN nanocomposites. From the result of the transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy, they confirmed that GNO was successfully prepared and deoxygenated. Based on the direct electrochemistry of ChOx along with an apparent rate constant of 2.69 per second, this

Recent progress in the graphene

35

cholesterol biosensor was prepared. They reported that the biosensor having a linear response toward the cholesterol within the range of 0.005–1.0  mM along with the detection limit of 0.715 μM (S/N = 3). They also reported that the apparent MichaelisMenten constant was 17.39 μM that was much lower than the Cao et al. biosensor and this indicated that the immobilized enzymes had high enzymatic activity.

2.9 GN based biosensor for bacteria One of the major scientific challenges and problems is too specific and sensitive detection of the pathogenic microorganism. At the current time, detection of the pathogenic microorganism is done based on culturing microorganisms on the agar plate method which takes a minimum of 24 h and sometimes they do not detect the noncultural cells. Huang et al. [54] prepared a fast, label-free, highly sensitive, and selective graphenebased biosensor for the detection of bacterial Escherichia coli. They achieved a detection limit as low as 10 cfu/mL. They equipped the biosensor with specific recognition elements that might be detected similar types of pathogens for diagnosis and food or environmental monitoring. These nanoelectronic biosensors were developed based on one-dimensional semiconducting nanomaterials and then they interfaced these biosensors with the mammalian cells to measure the dynamic activities. Nanoelectronic biosensors based on two-dimensional graphenes are used for the detection of bacterial metabolic activity in real time and gave an effective platform for functional studies or the screening of antibacterial drugs. For detection of the bacteria and their metabolic activities, G-FET cells were applied. The CVD graphene was modified with the anti-E. coli antibodies that allowed the detection of the concentration of the E. coli as low concentration up to 10 cfu/mL [43]. On water-soluble silk graphene was printed and then modified with the antimicrobial peptides and then for selective detection of bacteria at single-cell levels they modified with antimicrobial peptides [55].

2.10 Conclusion In this chapter, we tried to cover different examples of highlighted diseases in which graphene-based biosensors can be used effectively. Graphene is a very promising material for the biosensor due to their different physiochemical properties, like high specific surface area, single-layer thickness, pie-pie conjugations, etc. Preparation of the graphene and graphene-based biosensor is easy. CVD methods are the most effective methods for the preparation of mono or bilayer graphene sheets. GO and rGO were prepared from graphite precursor by solution-based exfoliation by weakening the van der wall forces of graphene layers. This is the most commonly used method for the preparation of graphene-based biosensors. Different methods like drop-casting, spin-coating, electrostatic interaction between positively charged interfaces and the negatively charged GO/rGO nanosheets, EPD, and electrochemical reduction of GO are used for coating the chemically derived graphene. This graphene-based biosensor

36

Functionalized Nanomaterial-Based Electrochemical Sensors

showed better sensitivity and selectivity toward glucose, protein makers, cholesterol, Hb, DNA, and bacteria. Some of the literature showed that the graphene-based biosensor is used for the treatment of different diseases like bronchitis, intestinal infection nephron diseases, etc. But also in some literature reviews, they found that in some biological samples like urine detection results failed to achieve the desired result. So more challenges are still left to be completed.

References [1] R.L. Siegel, K.D. Miller, A. Jemal, Cancer statistics, CA Cancer J. Clin. 69 (2019) 7–34. [2] S.P. Mohanty, E. Kougianos, Biosensors: a tutorial review, IEEE Potentials 25 (2) (2006) 35–40. [3] A. Darwish, A.E. Hassanien, Wearable and implantable wireless sensor network solutions for healthcare monitoring, Sensors 11 (6) (2011) 5561–5595. [4] R. Huang, N. He, Z. Li, Recent progresses in DNA nanostructure-based biosensors for detection of tumor markers, Biosens. Bioelectron. 109 (2018) 27–34. [5] T. Xu, N. Scafa, L.P. Xu, S. Zhou, K.A. Al-Ghanem, S. Mahboob, B. Fugetsu, X. Zhang, Electrochemical hydrogen sulfide biosensors, Analyst 141 (4) (2016) 1185–1195. [6] C.M. Hussain, Handbook of Nanomaterials for Industrial Applications, Elsevier, 2018. [7] C.M. Hussain, Handbook of Environmental Materials Management, Elsevier, 2019. [8] H. Mader, X. Li, S. Saleh, M. Link, P. Kele, O.S. Wolfbeis, Fluorescent silica nanoparticles, Ann. N. Y. Acad. Sci. 1130 (1) (2008) 218–223. [9] J.G. Manjunatha, M. Deraman, N.H. Basri, I.A. Talib, Fabrication of poly (Solid Red A) modified carbon nano tube paste electrode and its application for simultaneous determination of epinephrine, uric acid and ascorbic acid, Arab. J. Chem. 11 (2018) 149. [10] V. Vaijayanthimala, H.C. Chang, Functionalized fluorescent nanodiamonds for biomedical applications, Nanomedicine (Lond.) 4 (2009) 47–55. [11] C. Raril, J.G. Manjunatha, A simple approach for the electrochemical determination of vanillin at ionic surfactant modified graphene paste electrode, Microchem. J. (2019) 104575, https://doi.org/10.1016/j.microc.2019.104575. [12] J.G. Manjunatha, M. Deraman, Graphene paste electrode modified with sodium dodecyl sulfate surfactant for the determination of dopamine, ascorbic acid and uric acid, Anal. Bioanal. Electrochem. 9 (2017) 198. [13] S.M. Sharker, Hexagonal boron nitrides (white graphene): a promising method for cancer drug delivery, Int. J. Nanomedicine 14 (2019) 9983. [14] X. Chen, A.R. McDonald, Functionalization of two‐dimensional transition‐metal dichalcogenides, Adv. Mater. 28 (27) (2016) 5738–5746. [15] J. Shi, J. Lyu, F. Tian, M. Yang, A fluorescence turn-on biosensor based on graphene quantum dots (GQDs) and molybdenum disulfide (MoS2) nanosheets for epithelial cell adhesion molecule (EpCAM) detection, Biosens. Bioelectron. 93 (2017) 182–188. [16] M.H. Köhler, J.P. Abal, G.V. Soares, M.C. Barbosa, Molybdenum and tungsten disulfide as novel two-dimensional nanomaterials in separation science, in: Two-Dimensional (2D) Nanomaterials in Separation Science, Springer, 2021. [17] M. Holzinger, A.L. Goff, S. Cosnier, Nanomaterials for biosensing applications: a review, Front. Chem. 2 (2014) 63. [18] A.B. Chinen, C.M. Guan, J.R. Ferrer, S.N. Barnaby, T.J. Merkel, C.A. Mirkin, Nanoparticle probes for the detection of cancer biomarkers, cells, and tissues by fluorescence, Chem. Rev. 115 (19) (2015) 10530–10574.

Recent progress in the graphene

37

[19] N. Yang, X. Chen, T. Ren, P. Zhang, D. Yang, Carbon nanotube based biosensors, Sens. Actuators B 207 (2015) 690–715. [20] K.S. Novoselov, A.K. Geim, The rise of graphene, Nat. Mater. 6 (3) (2007) 183–191. [21] D. Chen, H. Feng, J. Li, Graphene oxide: preparation, functionalization, and electrochemical applications, Chem. Rev. 112 (11) (2012) 6027–6053. [22] S. Park, R.S. Ruoff, Chemical methods for the production of graphenes, Nat. Nanotechnol. 4 (4) (2009) 217–224. [23] V. Georgakilas, M. Otyepka, A.B. Bourlinos, V. Chandra, N. Kim, K.C. Kemp, P. Hobza, R. Zboril, K.S. Kim, Functionalization of graphene: covalent and non-covalent approaches, derivatives and applications, Chem. Rev. 112 (11) (2012) 6156–6214. [24] W. Choi, I. Lahiri, R. Seelaboyina, Y.S. Kang, Synthesis of graphene and its applications: a review, Crit. Rev. Solid State Mater. Sci. 35 (1) (2010) 52–71. [25] M. Pumera, Electrochemistry of graphene: new horizons for sensing and energy storage, Chem. Rec. 9 (4) (2009) 211–223. [26] O. Zagorodko, J. Spadavecchia, A.Y. Serrano, I. Larroulet, A. Pesquera, A. Zurutuza, R. Boukherroub, S. Szunerits, Highly sensitive detection of DNA hybridization on commercialized graphene-coated surface plasmon resonance interfaces, Anal. Chem. 86 (22) (2014) 11211–11216. [27] H. Sun, L. Wu, W. Wei, X. Qu, Recent advances in graphene quantum dots for sensing, Mater. Today 16 (11) (2013) 433–442. [28] Z. Sun, Z. Yan, J. Yao, E. Beitler, Y. Zhu, J.M. Tour, Growth of graphene from solid carbon sources, Nature 468 (7323) (2010) 549–552. [29] X. Dong, Y. Shi, Y. Zhao, D. Chen, J. Ye, Y. Yao, F. Gao, Z. Ni, T. Yu, Z. Shen, Y. Huang, Symmetry breaking of graphene monolayers by molecular decoration, Phys. Rev. Lett. 102 (13) (2009) 135501. [30] X.C. Dong, H. Xu, X.W. Wang, Y.X. Huang, M.B. Chan-Park, H. Zhang, L.H. Wang, W. Huang, P. Chen, 3D graphene–cobalt oxide electrode for high-performance supercapacitor and enzymeless glucose detection, ACS Nano 6 (4) (2012) 3206–3213. [31] Y. Huang, X. Dong, Y. Shi, C.M. Li, L.J. Li, P. Chen, Nanoelectronic biosensors based on CVD grown graphene, Nanoscale 2 (8) (2010) 1485–1488. [32] H. Maaoui, S.K. Singh, F. Teodorescu, Y. Coffinier, A. Barras, R. Chtourou, S. Kurungot, S. Szunerits, R. Boukherroub, Copper oxide supported on three-dimensional ­ammonia-doped porous reduced graphene oxide prepared through electrophoretic deposition for non-enzymatic glucose sensing, Electrochim. Acta 224 (2017) 346–354. [33] Y.H. Li, L. Zhang, J. Huang, R.P. Liang, J.D. Qiu, Fluorescent graphene quantum dots with a boronic acid appended bipyridinium salt to sense monosaccharides in aqueous solution, Chem. Commun. 49 (45) (2013) 5180–5182. [34] Y.R. Kim, S. Bong, Y.J. Kang, Y. Yang, R.K. Mahajan, J.S. Kim, H. Kim, Electrochemical detection of dopamine in the presence of ascorbic acid using graphene modified electrodes, Biosens. Bioelectron. 25 (10) (2010) 2366–2369. [35] T.Y. Chen, P.T. Loan, C.L. Hsu, Y.H. Lee, J.T. Wang, K.H. Wei, C.T. Lin, L.J. Li, Labelfree detection of DNA hybridization using transistors based on CVD grown graphene, Biosens. Bioelectron. 41 (2013) 103–109. [36] M. Zhou, Y. Zhai, S. Dong, Electrochemical sensing and biosensing platform based on chemically reduced graphene oxide, Anal. Chem. 81 (14) (2009) 5603–5613. [37] H.T. Dan Li, X. Li, Z. An, W. Li, W. Liu, X. Zhang, Q. Wang, Application of graphene oxide to the construction of electrochemical biosensor for environmental monitoring, in: TMS 2013 142nd Annual Meeting and Exhibition, Annual Meeting, 2013 Feb 22, p. 25. [38] T. Tian, Z. Li, E.C. Lee, Sequence-specific detection of DNA using functionalized graphene as an additive, Biosens. Bioelectron. 53 (2014) 336–339.

38

Functionalized Nanomaterial-Based Electrochemical Sensors

[39] Y. Bo, H. Yang, Y. Hu, T. Yao, S. Huang, A novel electrochemical DNA biosensor based on graphene and polyaniline nanowires, Electrochim. Acta 56 (6) (2011) 2676–2681. [40] L. Zhu, L. Luo, Z. Wang, DNA electrochemical biosensor based on thionine-graphene nanocomposite, Biosens. Bioelectron. 35 (1) (2012) 507–511. [41] Y. Yang, M. Kang, S. Fang, M. Wang, L. He, J. Zhao, H. Zhang, Z. Zhang, Electrochemical biosensor based on three-dimensional reduced graphene oxide and polyaniline nanocomposite for selective detection of mercury ions, Sens. Actuators B 214 (2015) 63–69. [42] A. Kakatkar, T.S. Abhilash, R. De Alba, J.M. Parpia, H.G. Craighead, Detection of DNA and poly-l-lysine using CVD graphene-channel FET biosensors, Nanotechnology 26 (12) (2015) 125502. [43] L. Lin, Y. Liu, L. Tang, J. Li, Electrochemical DNA sensor by the assembly of graphene and DNA-conjugated gold nanoparticles with silver enhancement strategy, Analyst 136 (22) (2011) 4732–4737. [44] L. He, Q. Wang, D. Mandler, M. Li, R. Boukherroub, S. Szunerits, Detection of folic acid protein in human serum using reduced graphene oxide electrodes modified by folic-acid, Biosens. Bioelectron. 75 (2016) 389–395. [45] L. He, Q. Pagneux, I. Larroulet, A.Y. Serrano, A. Pesquera, A. Zurutuza, D. Mandler, R. Boukherroub, S. Szunerits, Label-free femtomolar cancer biomarker detection in human serum using graphene-coated surface plasmon resonance chips, Biosens. Bioelectron. 89 (2017) 606–611. [46] D.J. Kim, I.Y. Sohn, J.H. Jung, O.J. Yoon, N.E. Lee, J.S. Park, Reduced graphene oxide field-effect transistor for label-free femtomolar protein detection, Biosens. Bioelectron. 41 (2013) 621–626. [47] M. Singh, M. Holzinger, M. Tabrizian, S. Winters, N.C. Berner, S. Cosnier, G.S. Duesberg, Noncovalently functionalized monolayer graphene for sensitivity enhancement of surface plasmon resonance immunosensors, J. Am. Chem. Soc. 137 (8) (2015) 2800–2803. [48] A. Vasilescu, S. Gáspár, M. Gheorghiu, S. David, V. Dinca, S. Peteu, Q. Wang, M. Li, R. Boukherroub, S. Szunerits, Surface Plasmon resonance based sensing of lysozyme in serum on Micrococcus lysodeikticus-modified graphene oxide surfaces, Biosens. Bioelectron. 89 (2017) 525–531. [49] T. Demeritte, B.P. Viraka Nellore, R. Kanchanapally, S.S. Sinha, A. Pramanik, S.R. Chavva, P.C. Ray, Hybrid graphene oxide based plasmonic-magnetic multifunctional nanoplatform for selective separation and label-free identification of Alzheimer’s disease biomarkers, ACS Appl. Mater. Interfaces 7 (24) (2015) 13693–13700. [50] H. Xu, H. Dai, G. Chen, Direct electrochemistry and electrocatalysis of hemoglobin protein entrapped in graphene and chitosan composite film, Talanta 81 (1–2) (2010) 334–338. [51] W. Sun, F. Hou, S. Gong, L. Han, W. Wang, F. Shi, J. Xi, X. Wang, G. Li, Direct electrochemistry and electrocatalysis of hemoglobin on three-dimensional graphene modified carbon ionic liquid electrode, Sens. Actuators B 219 (2015) 331–337. [52] S. Cao, L. Zhang, Y. Chai, R. Yuan, Electrochemistry of cholesterol biosensor based on a novel Pt–Pd bimetallic nanoparticle decorated graphene catalyst, Talanta 109 (2013) 167–172. [53] Z. Li, C. Xie, J. Wang, A. Meng, F. Zhang, Direct electrochemistry of cholesterol oxidase immobilized on chitosan–graphene and cholesterol sensing, Sens. Actuators B 208 (2015) 505–511. [54] Y. Huang, X. Dong, Y. Liu, L.J. Li, P. Chen, Graphene-based biosensors for detection of bacteria and their metabolic activities, J. Mater. Chem. 21 (33) (2011) 12358–12362. [55] M.S. Mannoor, H. Tao, J.D. Clayton, A. Sengupta, D.L. Kaplan, R.R. Naik, N. Verma, F.G. Omenetto, M.C. McAlpine, Graphene-based wireless bacteria detection on tooth enamel, Nat. Commun. 3 (1) (2012) 1–9.

Section B Fabrication of functionalized nanomaterial-based electrochemical sensors platforms

This page intentionally left blank

Application of hybrid nanomaterials for development of electrochemical sensors

3

Thiago C. Canevari Chemistry Course, Engineering School, Mackenzie Presbyterian University, São Paulo, SP, Brazil

3.1 Introduction Electrochemical sensors belong to the class of chemical sensors that can be formed by different nanomaterials that provide electroactive, can be used for real-time monitoring, in different media, and are less expensive compared to complex analytical ­instruments. Nanotechnology is considered a branch of science that aims to ­manipulate individual atoms and molecules with a diameter of up to 100 nm [1]. Based on this concept, the development of hybrid nanomaterials with different properties from primitive nanomaterials is increasingly attracting the attention of researchers. These hybrid nanomaterials are constituted by the intimate combination of different nanomaterials resulting in a single nanomaterial with additional physical-chemical properties, increasing the applicability of these nanomaterials in different areas, mainly in the development of electrochemical sensors [2–13]. The electrochemical sensors based on hybrid nanomaterials will present multifunctionalities and different applications, when compared to isolated nanomaterials, materials with micro dimensions (10− 6 m), and in bulk form. The main hybrid nanomaterials that are descript here will be SiO2/ MWCNTs, SiO2/MWCNTs/AgNPS, rGO/Sb2O5, Carbon dots/Fe3O4, rGO/Carbon dots, and rGO/Carbon dots/ AuNPs. These hybrid nanomaterials have been used to modify the surface of glassy carbon and screen-printed electrode and have been employed for electrochemical determination of dopamine, uric acid, paracetamol, epinephrine, dihydroxybenzenes isomers, disruptor endocrine bisphenol A, NADH, and fenitrothion pesticide in real samples.

3.2 SiO2/MWCNTs, SiO2/MWCNTs/AgNPS, and GO/Sb2O5 Hybrid materials formed based on mesoporous silica (SiO2) [14], obtained by the solgel process, have excellent characteristics to be used as platforms for the development of electrochemical sensors, such as ease of functionalization due to silanol groups (Si-OH), chemical and thermal stability and high porosity that allows the immobilization of different species and facilitates the load transfer process. Mesoporous silica is usually obtained by means of structure-guiding agents, templates [15]; however, here Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00002-8 Copyright © 2022 Elsevier Ltd. All rights reserved.

42

Functionalized Nanomaterial-Based Electrochemical Sensors

we will report works in which the mesopores were formed only through the use of HF, fluoride ions [16]. Multiwalled carbon nanotubes (MWCNTs) and graphene oxide (GO) have been widely used in the development of hybrid materials that are used for the construction of electrochemical sensors, due to their high electrical conductivity due to having sp2 bonds between carbon atoms and ease of functionalization due to the presence of different functional groups [17]. Thus, the mesoporous hybrid material, SiO2/MWCNTs, in which the disordered mesoporous structure was formed through the sol-gel process using HF, as a catalyst, has presented pores with an average diameter of 12 nm. This mesoporous structure favored the incorporation of functionalized MWCNTs, after acid treatment, as shown by XRD (Fig. 3.1A), SEM (Fig. 3.1B), and HR-TEM (Fig. 3.1C), allowing this hybrid material to present good electrocatalytic response to the simultaneous determination of dopamine, paracetamol, and uric acid in real samples (Fig. 3.1D–F) [18]. As can be seen, in Fig. 3.1D and E, the vitreous carbon electrode modified with SiO2/MWCNT/func showed better electrocatalytic response and comparison with the modification only with MWCNT/func due to the mesoporous structure guiding the nanotubes increasing the electrocatalytic efficiency, in addition to favor the transfer of charge. The direct synthesis of silver nanoparticles (AgNPs) in the SiO2/MWCNT func material gave rise to the SiO2/MWCNT/AgNPs nanomaterial that was used to develop the electrochemical sensor for the determination of phenolic isomers, hydroquinone, catechol, and resorcinol, simultaneously. Metallic nanoparticles are widely used for the development of platforms to be used as electrochemical sensors because they have improved the charge transfer process at the electrode-solution interface, improving the sensitivity of the electrochemical sensor [19]. The formation of AgNPs was confirmed by the technique of X-ray photoelectronic spectroscopy (XPS), Fig. 3.2A, and by means of HR-TEM micrographs (Fig. 3.2B). Fig. 3.2C–E shows the excellent performance of the vitreous carbon electrode modified with SiO2/MWCNT/AgNPs in relation to a simultaneous determination of phenolic isomers in a real sample [20]. The binding energy values of the spin-orbit components Ag 3d3/2 and Ag 3d5/2 at 374.4 and 368.3 eV confirm the formation of the AgNPs. The peaks at 379.7 and 373.6 eV show the presence of AgO species on the material surface in which the formation of the SiOAg bond on the surface of the nanomaterial is suggested. Fig. 3.2E shows that the functionalization of the hybrid nanomaterial with AgNPs significantly improved the electrocatalytic performance of the modified GCE in relation to the determination of phenolic isomers simultaneously. The rGO/Sb2O5 nanomaterial served as a platform for the development of a biosensor for the determination of endocrine interferon estriol [21]. The excellent response of the biosensor was due to the functionalization of the GO/Sb2O5 nanomaterial by the laccase enzyme, through covalent bonds between the enzyme and the functional groups present on the surface of the nanomaterial. The formation of Sb2O5 on the surface promoted the reduction of GO giving rise to rGO/Sb2O5 proven by XPS (Fig. 3.3).

Fig. 3.1  (A) XRD spectrum of mesoporous silica (SiO2) and the SiO2/MWCNT/func hybrid material, (B) SEM image of the SiO2/MWCNT/ func material, (C) HR-TEM micrographs of SiO2/MWCNT/func, (D) differential pulse voltammograms of dopamine (DA), uric acid (UA), and paracetamol (PAR) at MWCNT/func/GCE (inset figure bare GCE), and (E) SiO2/MWCNT/func/GCE. Measurements were performed with the same concentrations of 4.0 × 10− 5 mol L− 1 dopamine, uric acid, and paracetamol in PBS, pH 7.0. (F) Simultaneous determination of dopamine (DA), uric acid (AU), and paracetamol (PAR) at the SiO2/MWCNT/func/GCE electrode, dopamine concentrations ranged from 1.33 × 10− 6 to 4.64 × 10− 6 mol L− 1 and concentrations of uric acid and paracetamol ranged from 6.7 × 10− 7 to 4.65 × 10− 6 mol L− 1, in PBS, pH 7.0. Courtesy of T.C. Canevari, P.A. Raymundo-Pereira, R. Landers. E.V. Benvenutti, S.A.S. Machado, Sol–gel thin-film based mesoporous sílica and carbono nanotubes for the determination of dopamine, uric acid and paracetamol in urine. Talanta 116 (2013) 726–735. Copyright (2013), with permission from Elsevier.

Fig. 3.2  (A) XPS spectra of the Ag/SiO2/MWCNT hybrid material: Binding energy values of Ag3d, (B) HR-TEM micrographs of the Ag/SiO2/MWCNT material, (C) Cyclic voltammetry profiles for three different electrodes (Ag/SiO2/MWCNT/GCE, SiO2/MWCNT/GCE, and bare GC) in PBS buffer solution, pH 7, (D) bare glassy carbon electrode. Measurements performed with fixed concentrations of hydroquinone/ catechol (2 × 10− 5 mol L− 1) and resorcinol (6 × 10− 5 mol L− 1) in PBS, pH 7.0, (E) Squarewave voltammograms of hydroquinone (HQ), catechol (Cat), and resorcinol (Res): Comparison of Ag/SiO2/MWCNT/GCE and SiO2/MWCNT/GCE. Courtesy of T.C. Canevari, P.A. Raymundo-Pereira, R. Landers, S.A.S. Machado, Direct synthesis of Ag nanoparticles incorporated on a mesoporous hybrid material as a sensitive sensor for the simultaneous determination of dihydroxybenzenes isomers. Eur. J. Inorg. Chem. (2013) 5746–5754. Copyright © 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.

Fig. 3.3  Schematic display of the steps involved in the preparation of the rGO/Sb2O5 nanohybrid and the Lac/rGO/Sb2O5/GCE enzyme electrode and XPS spectra of rGO/Sb2O5. Courtesy of F.H. Cincotto, T.C. Canevari, S.A.S. Machado, A. Sánchez, M.A.R. Barrio, R. Villalonga, J.M. Pingarrón, Reduced graphene oxide-Sb2O5 hybrid nanomaterial for the design of a laccase-based amperometric biosensor for estriol, Electrochim. Acta 174 (2015) 332–339. Copyright (2015), with permission from Elsevier.

46

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 3.4  Cyclic voltammograms recorded at the GCE (a), rGO/GCE (b), rGO/Sb2O5/GCE (c), Lac/GO/GCE (d) and Lac/rGO/Sb2O5/GCE (e) for 2.0 μM estriol in 0.1 M sodium phosphate buffer, pH 7.0, containing 1.0 mM thionine as mediator; v = 50 mV/s and typical current-time responses for successive addition of 5.0 × 10− 5 mol L− 1 estriol in the presence of 1.0 mmol L− 1 thionine in 0.1 mol L− 1 PBS (pH 7) at the Lac/rGO/Sb2O5/GCE. Estriol concentration range between 0.025 and 1.025 μmol L− 1. Courtesy of F.H. Cincotto, T.C. Canevari, S.A.S. Machado, A. Sánchez, M.A.R. Barrio, R. Villalonga, J.M. Pingarrón, Reduced graphene oxide-Sb2O5 hybrid nanomaterial for the design of a laccase-based amperometric biosensor for estriol, Electrochim. Acta 174 (2015) 332–339. Copyright (2015), with permission from Elsevier.

Fig. 3.4 shows that the vitreous carbon electrode (GCE) modified with Lac/rGO/ Sb2O5 showed a better electrocatalytic response in relation to estriol when compared to the modified electrode with other nanomaterials. Lac/rGO/Sb2O5/GCE presented a good detection limit for estriol (11 nM), calculated using the chronoamperometry technique, being used to determine estriol in real samples.

3.3 Carbon dots/Fe3O4 and rGO/carbon dots Carbon dots are a new class of carbon-based nanomaterials [22] with a 0D structure, which can be crystalline or amorphous, depending on the synthesis process. These nanomaterials are characterized by their luminescence due to their small size ­(0–10 nm) that favors the effects of quantum confinement [23]. Another characteristic is that they are biocompatible and easy to function due to the presence of different functional groups, being widely used in the development of electrochemical (bio)sensors [24,25]. Nanomagnetite, Fe3O4, is also used in the development of electrochemical (bio) sensors [26,27] due to having as main characteristic high electron transfer rate, functional groups on their surface that allow functionalization with other species, in addition, to present magnetic properties, which, in the presence of a magnet, helps in the better distribution of nanomaterials on the surface of the electrodes, allowing a better electrocatalytic response in relation to the studied analytes.

Application of hybrid nanomaterials for development of electrochemical sensors 47

In this context, the combination of Fe3O4 with Cdots, obtained using the chronoamperometry technique [28], gave rise to the functional nanomaterial, Fe3O4/Cdots, which was used as a platform for modifying the printed and carbon electrode (SPE), in which a magnet on the back of the electrode to achieve a better distribution of the nanomaterial on the electrode surface, giving rise to SPE/Fe3O4/Cdots [29]. This electrode has presented a good electrocatalytic response to NADH (LD = 20 nM) in real samples, in addition to not being significantly interfered with by the main interferers in the determination of NADH. Carbon dots were also used as a reducing agent in the process of reducing graphene oxide (GO), without the use of conventional reducing agents, giving rise to the functional nanomaterial, rGO-Cdots [30]. This nanomaterial has been used to modify the surface of the printed carbon electrode (SPC), which showed good electrocatalytic activity for the determination of bisphenol A, in water, with a detection limit of 1 nM. The process of reducing GO by Cdots was confirmed by Raman spectroscopy in which there were changes in bands D and G. Fig. 3.5 shows HR-TEM, Raman spectra, and electrocatalytic response of modified electrodes. As can be seen in Fig.  3.5, the formation of the functional nanomaterial, rGOCNPs, showed a better electrocatalytic response compared to the other isolated nanomaterials (GO and Cdots). The best electrocatalytic response is demonstrated by the higher current intensity for a concentration of 1 × 10− 6 mol L− 1 of bisphenol A.

3.4 rGO/carbon dots/AuNPs Metallic nanoparticles (MNPs) are much utilized in electrochemical devices, mainly electrochemical sensor development due to improving electron transference onto electrode-solutions interface [19]. Take into account the high diversity of metallic nanoparticles, the gold nanoparticles (AuNPs) have had been most used due to present specific characteristics such as easy functionalization, an increase of surface area that results in the increase of sensitivity of electrode besides to present plasmonic effect [31,32]. Therefore, the synergic effect of a combination of reduced graphene oxide (rGO) and carbon dots (Cdots) with AuNPs promotes good characteristic for this nanocomposite to be used as a platform for electrochemical sensor development. As can be seen, Fig. 3.6 shows Raman spectra and HR-TEM micrographs of nanocomposite rGO-AuNPs-Cdots [33]. The Raman spectra (Fig. 3.6a) confirm the reduction of GO by incorporation of Cdots/AuNPs for changes at intensity Raman and shifts of G and B bands of the rGO-AuNPs-Cdots nanocomposite. The HR-TEM micrographs (Fig. 3.6b) show that Cdots and AuNPs have been incorporated and they have well distributed onto graphene oxide. Fig. 3.7 shows that the rGO-AuNPs-Cdots nanocomposite presents a good electrocatalytic response in the relation to phenolic isomers. In Fig. 3.7A, the rGO-AuNPsCdots nanocomposite has shown better activity in relation to the other nanomaterials that have been used to modify the glassy carbon electrode and have been employed in

Fig. 3.5  HR-TEM images at different magnifications of nanomaterials GO (A, B) and rGO-CNPs (C) and CNPs (D), Raman spectra of the GO and rGO-CNPs nanomaterials. (Figure inserted: Raman spectrum of the graphite used in the preparation of the GO.) Electrocatalytic responses of the cleaned carbon electrode (SPE) and modified with GO nanomaterials (SPE-GO), carbon nanoparticles (SPE-CNPs), and rGO-CNPs (SPE-rGO-CNPs) in relation to the determination of the endocrine interfering bisphenol A. The measurements are performed employing differential pulse voltammetry; Determination of the endocrine interferent bisphenol A by the printed carbon electrode modified with rGO-CNPs (SPE-rGO-CNPs) using the technique of differential-pulse voltammetry; (B) Calibration curve I × [bisphenol A] obtained by electrode SPE-rGO-CNPs. Measurements were performed in phosphate buffer, pH 7.0. (Error bars 0.1%.) Courtesy of T.C. Canevari, M.V. Rossi, A.D.P. Alexiou, Development of an electrochemical sensor of endocrine disruptor bisphenol A by reduced graphene oxide for incorporation of spherical carbon nanoparticles, J. Electroanal. Chem. 832 (2019) 24–30. Copyright (2015), with permission from Elsevier.

Application of hybrid nanomaterials for development of electrochemical sensors 49

Fig. 3.6  (a) GO Raman spectra and (b) ternary nanocomposite rGO-AuNPs-Cdots. (A) High-resolution TEM micrographs for the ternary composite rGO-AuNPs-Cdots, (B) AuNPs, and (C) Cdots. Courtesy of R. Cesana, J.M. Gonçalves, R.M. Ignácio, M. Nakamura, V.M. Zamarion, H.E. Toma, T.C. Canevari, Synthesis and characterization of nanocomposite based on Reduced Graphene oxide - Gold nanoparticles - Carbon dots: Electroanalytical determination of Dihydroxybenzene Isomers simultaneously. J. Nanopart. Res. 22 (2020) 336–347. Copyright (2020), with permission from Spring Nature.

Fig. 3.7  See fig legend on next page

50

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 3.7  (A) Electrocatalytic responses of the cleaned glassy carbon electrode (a) and modified with CDots nanomaterials (b), AuNPs (c), AuNPs-Cdots (d), GO (e), GO-Cdots (f), and rGO-AuNPs-Cdots (g) CNPs in relation to simultaneous determination of the hydroquinone and catechol. The measurements are performed employing differential pulse voltammetry, acetate buffer, pH 5.5. (B) Simultaneous determination of hydroquinone (HQ) and catechol (CC) in the presence of resorcinol (RC) at the GCE-rGO-AuNPs-Cdots. Differential pulse voltammograms performed with different concentrations of isomers: hydroquinone and catechol from 7.5 × 10− 7 to 7.4 × 10− 6 mol L− 1, keeping the concentration of resorcinol constant at 15 × 10− 6 mol L− 1. (A) Courtesy of R. Cesana, J.M. Gonçalves, R.M. Ignácio, M. Nakamura, V.M. Zamarion, H.E Toma, T.C. Canevari, Synthesis and characterization of nanocomposite based on reduced graphene oxide—gold nanoparticles—carbon dots: electroanalytical determination of dihydroxybenzene isomers simultaneously, J. Nanopart. Res. 22 (2020) 336–347. Copyright (2020), with permission from Spring Nature. (B) Reprinted with permission from C.S. Lim, K. Hola, A. Ambrosi, R. Zboril, M. Pumera, Graphene and carbon quantum dots electrochemistry, Electrochem. Commun. 52 (2015) 75–79. Copyright (2020), with permission from Spring Nature.

the simultaneous determination of hydroquinone (HQ), catechol (CC), and resorcinol (RC). This result is because of the good synergic effect between rGO, carbon dots, and AuNPs that improve the electron transference process in the electrode-solution interface contend phenolic isomers. Fig. 3.7B shows HQ and CC simultaneous determination in presence of RC. As can be seen, the GCE modified with rGO-AuNPs-Cdots nanocomposite has presented a good electrocatalytic response being that the electrocatalytic current has increased with an increase simultaneous of concentration of HQ and CC. This electrode has presented a detection limit considering (S/N = 3), for hydroquinone and catechol, ­respectively, 1.2  × 10− 8 mol L− 1 and 9.6 × 10− 8 mol L− 1.

Application of hybrid nanomaterials for development of electrochemical sensors 51

3.5 Conclusion The development of functional nanomaterials that can be used as a platform for the construction of electrochemical (bio) sensors is a rapidly growing area in which there are infinite possibilities for different combinations of different materials and different functionalizations to develop highly selective and highly sensitive at electrochemical sensors. It is important to note that electrochemical (bio) sensors have good sensitivity for determining analytes in situ. This makes the development of new functional materials or nanocomposites to be used as a platform for the construction of electrochemical sensors gaining more and more attention.

Websites Orcid: https://orcid.org/0000-0002-4336-8097?lang=en. Researchgate: https://www.researchgate.net/profile/Thiago_Canevari.

References [1] S.M. Lindsay, Introduction to Nanoscience, Oxford University Press Inc., New York, 2010. [2] T.V. Basova, A.K. Ray, Review—Hybrid materials based on phthalocyanines and metal nanoparticles for chemiresistive and electrochemical sensors: a mini-review, ECS J. Solid State Sci. Technol. 9 (2020), 061001. [3] P.A. Pushpanjali, J.G. Manjunatha, Development of polymer modified electrochemical sensor for the determination of alizarin carmine in the presence of tartrazine, Electroanalysis (2020), https://doi.org/10.1002/elan.202060181. [4] C. Raril, J.G. Manjunatha, D.K. Ravishankar, S. Fattepur, G. Siddaraju, L. Nanjundaswamy, Validated electrochemical method for simultaneous resolution of tyrosine, uric acid, and ascorbic acid at polymer modified nano-composite paste electrode, Surf. Eng. Appl. Electrochem. 56 (2020) 415. [5] N. Hareesha, J.G. Manjunatha, Surfactant and polymer layered carbon composite electrochemical sensor for the analysis of estriol with ciprofloxacin, Mater. Res. Innov. 24 (2019) 349. [6] M.M. Charithra, J.G. Manjunatha, Enhanced voltammetric detection of paracetamol by using carbon nanotube modified electrode as an electrochemical sensor, J. Electrochem. Sci. Eng. 10 (2020) 29. [7] C. Raril, J.G. Manjunatha, A simple approach for the electrochemical determination of vanillin at ionic surfactant modified graphene paste electrode, Microchem. J. 154 (2020) 104575. [8] J.G. Manjunatha, A promising enhanced polymer modified voltammetric sensor for the quantification of catechol and phloroglucinol, Anal. Bioanal. Electrochem. 12 (2020) 893. [9] C.M. Hussain, Handbook of Functionalized Nanomaterials for Industrial Applications, Elsevier, 2020. [10] C.M. Hussain, Handbook of Manufacturing Applications of Nanomaterials, Elsevier, 2020.

52

Functionalized Nanomaterial-Based Electrochemical Sensors

[11] C.M. Hussain, Handbook of Industrial Applications of Polymer Nanocomposites, Elsevier, 2020. [12] C.M. Hussain, Handbook of Nanomaterials for Sensing Applications, Elsevier, 2020. [13] K.K. Reddy, H. Bandal, M. Satyanarayana, K.Y. Goud, K.V.G.T. Jayaramudu, J. Amalraj, H. Kim, Recent trends in electrochemical sensors for vital biomedical markers using hybrid nanostructured materials, Adv. Sci. 7 (2020) 1902980. [14] K.S.W. Sing, D. Everett, R.A.W. Haul, L. Moscou, R.A. Pierotti, J. Rouquerol, T. Siemieniewska, Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity, Pure Appl. Chem. 57 (1985) 603–619. [15] X.-Y. Yang, L.-H. Chen, Y. Li, J.C. Rooke, C. Sanchez, B.-L. Su, Hierarchically porous materials: synthesis strategies and structure design, Chem. Rev. 46 (2017) 481–558. [16] E. Reale, A. Leyva, A. Corma, C. Martínez, H. García, F. Rey, A fluoride-catalyzed sol– gel route to catalytically active non-ordered mesoporous silica materials in the absence of surfactants, J. Mater. Chem. 15 (2005) 1742. [17] V. Georgakilas, J.A. Perman, J. Tucek, R. Zboril, Broad family of carbon nanoallotropes: classification, chemistry, and applications of fullerenes, carbon dots, nanotubes, graphene, nanodiamonds, and combined superstructures, Chem. Rev. 115 (2015) 4744–4822. [18] T.C. Canevari, P.A. Raymundo-Pereira, R. Landers, E.V. Benvenutti, S.A.S. Machado, Sol–gel thin-film based mesoporous sílica and carbono nanotubes for the determination of dopamine, uric acid and paracetamol in urine, Talanta 116 (2013) 726–735. [19] J. Chazalviel, P. Allongue, On the origin of the efficient nanoparticle mediated electron transfer across a self-assembled monolayer, J. Am. Chem. Soc. 133 (2011) 762. [20] T.C. Canevari, P.A. Raymundo-Pereira, R. Landers, S.A.S. Machado, Direct synthesis of Ag nanoparticles incorporated on a mesoporous hybrid material as a sensitive sensor for the simultaneous determination of dihydroxybenzenes isomers, Eur. J. Inorg. Chem. (2013) 5746–5754. [21] F.H. Cincotto, T.C. Canevari, S.A.S. Machado, A. Sánchez, M.A.R. Barrio, R. Villalonga, J.M. Pingarrón, Reduced graphene oxide-Sb2O5 hybrid nanomaterial for the design of a laccase-based amperometric biosensor for estriol, Electrochim. Acta 174 (2015) 332–339. [22] X. Xu, R. Ray, Y. Gu, H.J. Ploehn, L. Gearheart, K. Raker, W.A. Scrivens, Electrophoretic analysis and purification of fluorescent single-walled carbon nanotube fragments, J. Am. Chem. Soc. 126 (2004) 12736–12737. [23] S.N. Baker, A. Gary, Baker, luminescent carbon nanodots: emergent nanolights, Angew. Chem. Int. Ed. 49 (2010) 6726–6744. [24] C.S. Lim, K. Hola, A. Ambrosi, R. Zboril, M. Pumera, Graphene and carbon quantum dots electrochemistry, Electrochem. Commun. 52 (2015) 75–79. [25] Y. Wang, A. Hu, Carbon quantum dots: synthesis, properties and applications, J. Mater. Chem. C 2 (2014) 6921–6939. [26] I.S. Kucherenko, O.O. Soldatkin, D.Y. Kucherenko, O.V. Soldatkina, S.V. Dzyadevych, Advances in nanomaterial application in enzyme-based electrochemical biosensors: a review, Nanoscale Adv. 1 (2019) 4560–4577. [27] I.A. Mattioli, P. Cervini, É.T.G. Cavalheiro, Screen-printed disposable electrodes using graphite-polyurethane composites modified with magnetite and chitosan-coated magnetite nanoparticles for voltammetric epinephrine sensing: a comparative study, Microchim. Acta 187 (2020) 318–330. [28] T.C. Canevari, M. Nakamura, F.H. Cincotto, F.M. de Melo, H.E. Toma, High performance electrochemical sensors for dopamine and epinephrine using nanocrystalline carbon quantum dots obtained under controlled chronoamperometric conditions, Electrochim. Acta 209 (2016) 464–470.

Application of hybrid nanomaterials for development of electrochemical sensors 53

[29] T.C. Canevari, F.H. Cincotto, D. Gomes, R. Landers, H.E. Toma, Magnetite nanoparticles bonded carbon quantum dots magnetically confined onto screen printed carbon electrodes and their performance as electrochemical sensor for NADH, Electroanalysis 29 (2017) 1968–1975. [30] T.C. Canevari, M.V. Rossi, A.D.P. Alexiou, Development of an electrochemical sensor of endocrine disruptor bisphenol A by reduced graphene oxide for incorporation of spherical carbon nanoparticles, J. Electroanal. Chem. 832 (2019) 24–30. [31] A. Merkoçi, Nanoparticles based electroanalysis in diagnostics applications, Electroanalysis 25 (2013) 15–27. [32] W. Yang, H. Liang, S. Ma, D. Wang, J. Huang, Gold nanoparticle based photothermal therapy: development and application for effective cancer treatment, Sustain. Mater. Technol. 22 (2019) e00109–e00115. [33] R. Cesana, J.M. Gonçalves, R.M. Ignácio, M. Nakamura, V.M. Zamarion, H.E. Toma, T.C. Canevari, Synthesis and characterization of nanocomposite based on reduced graphene oxide—gold nanoparticles—carbon dots: electroanalytical determination of dihydroxybenzene isomers simultaneously, J. Nanopart. Res. 22 (2020) 336–347.

This page intentionally left blank

Biofunctionalization of functionalized nanomaterials for electrochemical sensors

4

Muhammed Bekmezcia,b, Ramazan Bayata,b, Vildan Erdurana,b, and Fatih Sena a Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya, Turkey, bDepartment of Materials Science & Engineering, Faculty of Engineering, Dumlupınar University, Kütahya, Turkey

4.1 Introduction It is very important for humanity to follow and interpret the developments in our environment. Today, there are many developments in diagnosis, and process follow-up with multidisciplinary scientific studies. As a result of these studies, sensor technologies came to the forward. The most well-known sensor applications are electrochemical sensors. Electrochemical sensors are devices that provide real-time information about the composition of a system by connecting a chemically selective layer (recognition element) to an electrochemical transducer [1]. Electrochemical sensors are divided into different branches. One of them is biosensors. Biosensors focussing on electrochemical enzymes, a subset of chemical sensors, combine the strong enzyme sensitivity with electrochemical transducer accuracy. The electrodes used in the biosensor are enzyme electrodes. These electrodes are made up of electrochemical probes with a thin film of enzyme attached to the operating electrode layer. Modern enzyme-based tests with electrochemical and optical transduction systems can effectively calculate the concentration of glucose in human blood [2]. There are different studies to ensure stabilization in practice. For example; it has been revealed that the carbon nanotube electrode prepared by functionalizing Pd/Ni nanoparticles exhibits high electrocatalytic activity for the oxidation of glucose to gluconolactone [3]. As can be seen from this example; sensor technology based on nanomaterials such as nanoparticles, nanotubes, nanocables, with superior physical properties produced by nanotechnology, enables more selective, more sensitive, and low observable limit analyses in methods using electrochemical techniques for biomolecular detection [4]. In some biosensors, like all chemical sensors, the current instrumentation consists of a transducer that converts the reaction into a visible signal and a chemically specific layer that immediately isolates the response of the analyte. Analyte; electrical, sound, optical or thermal sensors or can be designed to detect a gas analysis [5]. Sensor applications have gained a wide field of study in recent years. These devices (emerged in the second half of the 20th century) are now used in a wide variety of commercial applications [6]. The reason why the research area is wide is that it contains many interesting features. The use of electrons for signal reception without undesirable data Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00003-X Copyright © 2022 Elsevier Ltd. All rights reserved.

56

Functionalized Nanomaterial-Based Electrochemical Sensors

generation is considered a properly functioning model for analytical applications; Shrinkage in portable devices should be low cost, which is another major advantage of this method. In addition, the development of electrochemical sensors helps the development of other techniques, such as chromatography [6]. Sensor life can be shortened by various environmental factors such as low humidity, high temperatures, and exposure to poisons [7]. As a result of the development of nanotechnological developments in the field of sensors, we observe that very successful systems have been established. This section discusses the overall study of the biological functions of nanostructured electrochemical sensors.

4.2 Biosensors Defining the events around us is very important to satisfy the curiosity of humanity. From the giant telescopes we set up to observe the universe, the microscopes that we invented to display nanoscale materials, from the devices we use to measure our heartbeat, it is always a manifestation of our curiosity to examine the facts that cause contamination of water or soil. A lot of research has been done to examine the facts and see the order again, and these researches bring beautiful ideas with each passing day. As a human being, he does a lot of research to examine the facts around him in a living dimension. At this point, biosensors are very popular. Enzyme biosensors are designed on immobilization methods, namely van der Waals forces, adsorption of ionic bonds, or covalent bonds. Oxidoreductases, polyphenol oxidases, peroxidases, and aminooxidases are enzymes widely used for this purpose [8–11]. Research and development of biosensors have a lot of attention today as a branch of science that is studied extensively. Because they are easy, fast, low cost, high precision, and highly selective technology [12]. These features are also the basis of its high use for diseases and environmental phenomena. The biosensor is defined as a device for the detection of chemical compounds by electrical, thermal, or optical signals using specific biochemical reactions mediated by isolated enzymes, immunosystems, tissues, organelles, or whole cells [13]. Biosensors can be classified into two types according to the physicochemical transduction mode or biocognition element type. According to the transducer type, biosensors can be classified as electrochemical, optical, thermal, and piezoelectric biosensors [14]. Each biosensor is functionally composed of three elements. The biological factor which determines the analyte and generates a response signal is the first part of the biosensor. The signal produced by the biological part is then transformed by the second component, called the converter, which is the most important component of any biosensing system, to a measurable response. The third component of the biosensor is the detector that uses an electronic imaging device to enhance and interpret signals before showing. The system is shown in Fig. 4.1. At this stage, an analyte comes to the sensor of the system and initiates a descriptive signal. Fig. 4.2 illustrates the working principle of biosensors.

Biofunctionalization of functionalized nanomaterials

57

Fig. 4.1  Schematic representation of the biosensor. Sensing, reading, and detecting parts of the sensor. From A.A. Gokhale, J. Lu, I. Lee, Recent progress in the development of novel nanostructured biosensors for detection of waterborne contaminants, Nanoscale Sensors (2013) 1–34. https:// doi.org/10.1007/978-3-319-02772-2_1.

Fig. 4.2  Working principle of the biosensor. The sensing, monitoring, and analyzing sections of the sensor are shown. From S.N. Sawant, Development of biosensors from biopolymer composites, in: Biopolymer Composites in Electronics, Elsevier Inc., 2017, pp. 353–383. https://doi.org/10.1016/ B978-0-12-809261-3.00013-9

Electrochemical biosensors are the most extensively researched biosensors because they offer low detection limits, specificity, construction simplicity, and convenience advantages. Thanks to the latest developments in electronic instrumentation, this type of biosensors can be miniaturized for in vivo monitoring, lab devices on the chip, or handheld devices for on-site monitoring [14]. Immunosensors rely on the great similarity

58

Functionalized Nanomaterial-Based Electrochemical Sensors

between the antibodies and the respective antigens, i.e., antigens specifically related to viruses or contaminants or connected to the component components of a host immune system. Various sensors were designed for various tasks. These sensors are described below and are used extensively in these sensors. Magnetic biosensors: These are instruments used to detect magnetic microphones and nanoparticles on microfluidic channels via magnetoresistance. Magnetic biosensors have tremendous promise in terms of accuracy and scale [15]. As previously stated, thermal biosensors or calorimetric biosensors are formed by translating the materials to a physical transducer [16,17]. The micro-balances of the quartz crystal and the acoustic surface wave unit are two types of piezoelectric biosensors. The measurement is based on changes in the frequency of resonance of the piezoelectric crystal due to mass structural changes [18]. The DNA-based biosensors are engineered to allow a single chain nucleic acid molecule to identify and bind its complementary strand in a sample. The interaction is caused by the creation of stable hydrogen bonds between the two nucleic acid strands [19]. The DNA-based biosensors are engineered to allow a single chain nucleic acid molecule to identify and bind its complementary strand in a sample. The interaction is caused by the creation of stable hydrogen bonds between the two nucleic acid strands [20]. The application areas of optical biosensors have expanded considerably. This can be said as evidence that advanced physical methods are best adaptable.

4.2.1 Electrochemical biosensors These sensor types are the oldest system among the known sensor systems. Electrochemical biosensors have a wide range of uses. There are many researches and systematic use in finding a lot of usage areas. The use of these sensor systems was made in the early stages for blood glucose determination. These sensor types are generally in the form of enzyme electrodes. Electrochemical biosensors are also available as amperometric, potentiometric, and conductive electrochemical biosensors [17]. Amperometric and voltammetric biosensors can be classified according to their own current potential relationships with the electrochemical system. Amperometric sensors are located in a subset of voltammetric sensors. A constant potential is applied to the electrochemical cells in amperometric sensors, and the associated current is then obtained through a reduction or oxidation reaction. However, a voltammetric sensor can operate in other linear or cyclic voltammetric modes, for example. As a result, the current and voltage will be different for each mode. Amperometric biosensors typically test concentration-dependent current using an electro-chemical electrode covered with biologically active content. The amperometric conversion is focused on electrode surface oxidation and removal of electroactive material [17]. An amperometric transducer can be used with any enzyme, antibody, DNA probe, and bio-sensing material including whole cells and tissues [21]. Potentiometric measurements consist of a non-Faradic electrode process with no net current flow and work on the principle of charge density accumulation on an electrode surface, resulting in significant voltage build-up on the electrode. Potentiometric

Biofunctionalization of functionalized nanomaterials

59

biosensors track changes in the electrical voltage resulting from the binding of an ion to the ionophore, using appropriate bioreceptors and compatible transducers. Potentiometric detection usually measures the voltage of either a product’s activity or the activity of a reaction in an electrochemical reaction within an electrochemical cell containing a biological sensing element [17]. Biosensors for conductivity, power, and impedance; they calculate numerous changes in the electric field. Such variations may be the general electrical conductivity of the solution or medium and the change in potential which depends on the electrode surface of the fixed layer which may also be expressed by the ability to demonstrate impedimetric reaction. Biosensors for early conductivity/impedance are focused on adjustments in conductivity induced by target analytes on mediators. Nevertheless, the solution’s resistance is measured by the movement of all ions involved, and calculations of conductivity are usually known to be fairly unknown. Monitoring variations in conductivity induced by the catalytic behavior of enzymes fixed in or on planar microelectronic conductive cells will solve this issue [22]. Most enzymes catalyze reactions, which causes general changes in the conductivity of the solution so that biosensors measuring conductivity also show great potential as sensing elements [17].

4.2.2 Sensor applications of nanomaterials Nanomaterials are used in many different fields. This is based on researching the best application reasons and optimizing the ideal conditions on the ideal material. Nanoparticles are also very efficient in sensor applications. Studies show that different applications of nanoparticles provide suitable conditions for sensors [23]. Nanoparticles: They have serious industrial researches and they make human life easier. This function is due to their superior chemical, physical and mechanical properties, and their outstanding formability, resulting in better performance than their traditional counterparts [24,25]. Material-related problems may arise in the creation of the sensors. No serious deficiencies were observed, especially during the creation of detection systems. Serious material researches were carried out to compensate for these shortcomings. The quest for materials with special molecular scale properties has culminated in tremendous industrial influence in diverse fields such as food processing, medicine, medicinal, cosmetics, nanocomposite products, biotechnology, biosensor systems, and renewable energy sources. It is expected that the interaction between nanoscience and nanotechnology, biology, and biomedicine will radically develop therapeutic treatments that bring traditional strategies and challenges [26]. The definition of nanomaterials can be described differently for each discipline. Although scientists have not yet met in a common decision, nanomaterials can be called all materials closest to the nanoscale [27,28]. It is also worth noting that the size of the material should not be used for identification purposes only. It will be appropriate to use the material type, shape, and purpose of use to define the nanomaterial. In addition, the rapid development of methods of duplicating and displaying the basic structures of molecules, their evaluation together with nanotechnology will cause the use of nucleotide-based biosensors to become more widespread [29,30]. The use of nanomaterial in a sensor is very important.

60

Functionalized Nanomaterial-Based Electrochemical Sensors

The basis for this is that the improvement of detection characteristics provides a serious advantage. Sensing speeds of sensor systems are very important. It is important not only for sensor quality, but also to minimize the greatest loss of humanity, time. Nanomaterials have been produced for use in these applications, and improvements continue to be made in this regard. The performance of the sensing materials depends critically on the microstructures that require the development of material processing techniques to achieve the desired microstructures and morphologies. To use nanomaterials in a sensor system, certain difficulties must be overcome. For nanomaterials, dimensional, heat load and volume problems arise. With the R&D studies carried out, efforts are underway to overcome these and similar problems in the nanoscale. Carbon nanotubes (CNTs) and graphite carbon electrodes are highly preferred due to an improved mass transport, high porosity, effective surface area over conventional electrodes. They also provide a convenient analysis environment. Sensors made with carbon nanotubes provide a very suitable sensor/biosensor environment [31]. For carbon-based sensor support materials, Graphene oxide is widely used in biological applications such as carbon nanotube and similar. Information was given about the advantages and disadvantages of these materials [32]. Another material widely used in sensor applications is aluminum. Aluminum matrix composites are preferred due to their superior selectivity properties. There are different application procedures. However, they are not preferred in biological system applications due to their nonbioinertness. Different gains have been achieved in sensor applications. Innovative research has been developed to detect biological, chemical, or physical changes [31,33–46].

4.2.3 Biofunctionalization of nanomaterials With the development of the science of nanomaterials, rapid progress has been made toward eliminating the disadvantages caused by materials. However, it is clear that the nanomaterials used in the biological field still have insufficient morphological properties. The development of biocompatible advanced functional materials is quite exciting in sensor studies. Owing to its various possible uses in materials research, medicine, and manufacturing, nanoparticles and other nanoscale materials are of considerable interest. Although biofunctionalization of nanomaterials is the main topic discussed in this section, it is vital for many studies that take into account living life. This fact is valid for sensor studies. In some studies, studies have been made to improve only the antibacterial or antiviral properties of nanomaterials [30]. The rational choice of therapeutically active biomolecules for the design of nanoparticles will increase bioavailability. The toxic properties and aggregation of these nanoparticles have limited their use in more optimized applications. The rational choice of therapeutically active biomolecules to function on the surface of these particles will increase biocompatibility and bioavailability [47]. Magnetic nanoparticles (MNPs), which have been recently studied to fulfill these requests, will lead to serious improvements for diagnostic and therapeutic applications [48,49]. These materials generally show superparamagnetic properties at room temperature [49]. Its magnetization is, however, usually random in the absence of this field, saturated in an existing magnetic field. These MNPs are very

Biofunctionalization of functionalized nanomaterials

61

useful to many experiments in the use of biomedical applications due to their special magnetic characteristics and biological capabilities. Around the same time, these magnetic particles have been researched thoroughly. They may be magnetically marked and detected with their reactions to external magnetic fields in experiments such as cancer release, monitoring, and identification of biological characteristics and therapy [30–33]. Moreover, these MNPs can respond resonantly to an outside magnetic field and serve as a heater for magnetic fluid hyperthermia which provides a potential therapeutic alternative. It can be used to communicate with functional probes. Moreover, multistage conjugations with one NP are typically poor efficiency operations, and their target potential is hindered by the inclusion of several molecules with the same NP surface, which then absorb NP conjugates. Recent advancements in NP technology have allowed the synthesis of composite NPs that have been used in single part MNPs, with core/shells and dumbbell architectures. Alternatively, FePt NPs, which are highly cytotoxic, have been found to release with adequate surface functionality [50]. Such NPs that are used as a therapeutic agent may provide a positive solution to the issue of multistage conjugation in delivery systems. Since only a targeting agent needs to be added to the NP surface, so the amount of targeting molecules can be easily regulated by the NP scale [51]. However, it should be noted that many different nanoparticles are also used in sensor applications. For example, many nanomaterials obtained by ceramic, metal, or green chemicals can be used in sensor technologies [52].

4.2.4 Applications in electrochemical sensors Electrochemical sensors are commonly used biosensors [53]. Electrochemical systems have been used for a very long time. However, in order to eliminate some of the missing features of these sensors, important biomaterials and nanomaterial researches are conducted. Biological recognition molecules in electrochemical biosensors bind on or near an electrochemically active interface with a specific analyte, which may contain nanomaterials that lead to a measurable signal. They are like receptors on the surface of cells. Normally in interaction with an electrode, the electrochemically active sensor, the electrical transducer or detector unit, transforms this biochemical reaction into an electrical signal which can be further enhanced by a signal processor. The signal processor involves a computer program transforming the electrical signal into a shape which can be viewed on a computer screen. Among the-converter forms in biosensors, with more than 2000 nanomaterials, optical, thermal, and magnetic sensors are developed [54]. In order to biofunction, studies were carried out to characterize the electrode surface coated with biocomposite film composed of chitosan‑gold nano-tyrosinase enzyme (K-Gnp-T) by electrochemical methods. Analytical performance of the developed biosensor was checked by amperometric determination of a phenolic compound, catechol [55]. Studies have revealed exciting situations. It is stated that the application is in an important position in terms of its cheapness, high sensitivity, and application surface to other probes [55]. The basis of the studies is what kind of positive effects it will bring to the biological feature. Biologically, a nanoparticle will be obtained first and

62

Functionalized Nanomaterial-Based Electrochemical Sensors

this is again desired to make a difference in a signal-sensing feature. Electrochemical biosensors have gained ample use in determining soil and water pollutants in the recent past. Many obstacles to using pesticides as amperometric, potentiometric, conductometric transducers, and field-effect transistors have been overcome with new studies [55]. Sensors usually depend on the enzymatic change and the change in the activity of the enzyme used in the system for the detection of these contaminants. It is equipped with enzyme, antibody, or DNA systems in the detection of these changes. Especially DNA biosensors will be used as important sensors in the near future. Because of their simple DNA testing procedures and instant on-site tests, these sensors are compact, quick, and precise, built for surgical, forensic, environmental, and pharmaceutical use [56]. In a study, a simple sensor was designed using poly (dl-phenylalanine) to detect riboflavin. The prepared sensor has been characterized in conventional practice. This sensor is designed; it provides a cheap and ideal selectivity for riboflavin detection [33]. There are many studies on electrochemical sensors. One of them is the study of Indigotin detection. A sensor designed by making surface material with TX-100 modified carbon paste provides a very fast, simple, and ideal environment [39]. If we need to give another valuable example for the studies; textile dye Alizarin Carmine (AC) is a type of sensor made for detection with modified carbon paste using the cyclic voltammetry technique. A valuable feature of this sensor is that it is made for the detection of harmful substances in living organisms [40]. This method is one of the good examples to be given for electrochemical sensors. In another study, a sensitive and selective sensor was designed for poly (adenine) film modified carbon nanotube paste electrode (PAEMCNTPE), dopamine (DA), uric acid (UA), and ascorbic acid prepared by electropolymerization of adenine on a carbon nanotube paste electrode. These studies are similar to other examples. These studies for electrochemical sensors are aimed at achieving an ideal sensor design [41,42]. In fact, the application use of a nanomaterial is as shown in Fig. 4.3. Covering any nanoparticle with a biological material provides an advantage to improve its electrochemical properties. Carbon nanoparticles are often used in sensor applications. However, there are serious problems in the use of CNTs in sensor studies. Important R&D activities are carried out to reduce these. Studies are being carried out to benefit from the large potential applications in many areas due to its unique structural, mechanical, and electronic features and to use more CNTs. Hybridization studies are carried out for the chemical functionalization of CNTs to overcome delays and margins of error from sensor sensors and extend the scope of their applications. In this way, electrochemical sensor applications will be used a lot [57]. Moreover, experiments are ongoing for a new glucose biosensor focused on immobilization of glucose oxidase in thin chitosan films comprising graphene on a gold electrode and gold nanoparticles (AuNPs) nanocomposite. These studies are carried out in order to expand [58]. These studies have shown that there are particularly improvements in their catalytic properties with joint studies. These applications have also been studied with palladium (Pt) materials, especially in glucose sensors. Sensitivity in the sensor is also reported using nanoparticles synthesized in layered layers [59]. The basis of this sensitivity can be evaluated as the morphological properties of Pt material to the sensor. Similarly, biosensors based on graphene demonstrated remarkable

Biofunctionalization of functionalized nanomaterials

63

Fig. 4.3  Functionalization of biomolecular nanoparticles with interface/binding agents for antibacterial applications. From M. Veerapandian, K. Yun, Functionalization of biomolecules on nanoparticles: specialized for antibacterial applications, Appl. Microbiol. Biotechnol. 90 (5) (2011) 1655–1667. Springer. https://doi.org/10.1007/s00253-011-3291-6.

performance with high sensitivity, wide linear detection ranges, low detection limits, and long-term stability. In the process that progresses in this field, it is aimed to overcome the needs of sensors and sensor technologies in a fast and low-cost way [60]. In another embodiment, they are electrochemical immunosensors. These sensors can be used as antibody-based affinity sensors, which have a high impact on clinical and biological detection analysis. We can state that there are too many dendrimers covered with electrodes for immunosensors [61]. In general, the analytical performance, construction, signal generation, and amplification of these devices are quite good. In recent applications in electrochemical biosensors, it is really interesting, focused on phenylboronic acid (PBA) and its derivatives. PBAs are known to selectively bind 1,2 and 1,3-diols in neutral, aqueous environments to form negatively charged boronate esters. Due to selective binding, it was used to create electrochemical glucose sensors. PBA-modified electrodes can also detect glycoproteins such as glycated hemoglobin (HbA1c), avidin, and serum albumin because they contain hydrocarbon chains on the surface [62]. By modifying such sensors with nanomaterials, selective efficient sensor technologies have been developed. One of the best examples of Aptamer applications

64

Functionalized Nanomaterial-Based Electrochemical Sensors

can be said of the efficiency obtained from the collaboration with sensors. Nucleic acid aptamer functionalized carbon nanomaterial-based electrochemical biosensors are a widely promising series of sensors for the identification of biomarkers linked to cancer, including nucleic acids, proteins, and cells. In addition to future developments, problems and problems are expected to be studied in practice with functionalized electrochemical biosensors based on nucleic acid aptamer based on carbon nanomaterials. These sensor types are very important and valuable in terms of using predominantly in the early diagnosis of diseases such as cancer [63]. Some of the literature-reported functionalization strategies derive from shortcomings such as intermediate synthesis measures, weak biocompatibility, low stability, and hydrophobic materials [54]. Coating techniques that are focused on chemisorption and ligand exchange typically have a stronger means of adjusting NPs’ surface properties. They may exhibit selective binding for NPs of good quality after combination with appropriate targeting ligands, antibodies, or proteins [64]. It provides the best examples of fluorescent imagery, magnetic resonance imaging (MRI), positron emission tomography (PET) imaging, and multimodal sensor systems in general [65]. In fact, these systems will be ­considered among the most important of the sensors that have been functionalized with a biological layer. Not only such diagnostic devices through the usage of specific biomarkers that can be monitored and tested using advanced analytical techniques have become part of the current medical detection and treatment of some diseases [66]. The ones mentioned here are those that have only the most applications of nanomaterials. Of course, the fact that biological materials and materials obtained through synthesis with advanced R&D studies and innovative synthesis methods will be used in sensor systems will be a very important scientific breakthrough [67]. It is preferred because of its nanoparticle properties, which are widely used in sensor applications [23].

4.3 Conclusion The usage areas of nanomaterials are quite high and they are increasing day by day. As mentioned in this section, different applications of different materials are mentioned in sensor applications. It is expected that usage areas will increase by developing NPs for different applications. Especially with the new devices to be obtained from these particles, it is expected that high-quality imaging systems will be obtained. NPs that will be obtained and show biological properties can be obtained as synthesis, coating, surface functionalization, and bioconjugation. By kneading NP surfaces with the most common strategies with bioengineering fundamentals, quality materials will be formed by obtaining the desired ligands by physical adsorption or chemisorption to the surface. Diagnostic tools relevant to cancer treatment are the most popular use of these techniques but neurological, respiratory, viral, inflammatory, and neurogenerative disorders are now used for many tools. High concentrations of such biomarkers in fairly complicated biological materials, including blood, render novel methods of identification challenging to establish. It is clear that the new types of bio nanomaterials to be obtained are very important for the acceleration of the process for the future.

Biofunctionalization of functionalized nanomaterials

65

Also with the emergence of effective diagnostic instruments completely designed, refined, and tested against conventional approaches used in clinical environments, the dynamic manufacturing mechanism of immunosensors and scaling up to further mass development complicates the development of commercially accessible products. Almost all the materials used in this process are expensive, which is quite expensive for sensor applications. Typically, significant difficulties in the production of sensors and the stage of operation are challenges in processing biological nanomaterials such as enzymes and antibodies. It will be possible to use these new types of sensor systems in the near future. However, it should be remembered that with the continuous improvements in molecular biology, nanofabrication methods and labeling, nano instrumentation capabilities, it will create fast, precise, selective, and efficient sensor systems.

References [1] F. Faridbod, V.K. Gupta, H.A. Zamani, Electrochemical sensors and biosensors, Int. J. Electrochem. (2011), https://doi.org/10.4061/2011/352546. [2] M. Adeel, M.M. Rahman, I. Caligiuri, V. Canzonieri, F. Rizzolio, S. Daniele, Recent advances of electrochemical and optical enzyme-free glucose sensors operating at physiological conditions, Biosens. Bioelectron. (2020) 112331, https://doi.org/10.1016/j.bios. 2020.112331. [3] H. Karimi-Maleh, K. Cellat, K. Arıkan, A. Savk, F. Karimi, F. Şen, Palladium–nickel nanoparticles decorated on functionalized-MWCNT for high precision non-enzymatic glucose sensing, Mater. Chem. Phys. 250 (2020) 123042, https://doi.org/10.1016/j. matchemphys.2020.123042. [4] S. Alwarappan, A. Erdem, C. Liu, C.Z. Li, Probing the electrochemical properties of graphene nanosheets for biosensing applications, J. Phys. Chem. C 113 (20) (2009) 8853–8857, https://doi.org/10.1021/jp9010313. [5] N.R. Stradiotto, H. Yamanaka, M.V.B. Zanoni, Electrochemical sensors: a powerful tool in analytical chemistry, J. Braz. Chem. Soc. 14 (2) (2003) 159–173, https://doi. org/10.1590/S0103-50532003000200003. Sociedade Brasileira de Quimica. [6] F.R. Simões, M.G. Xavier, Electrochemical sensors, in: Nanoscience and Its Applications, Elsevier Inc, 2017, pp. 155–178. [7] G.L. Anderson, D.M. Hadden, The Gas Monitoring Handbook, Ickus Guides, 1999. [8] P. Mehrotra, Biosensors and their applications—a review, J. Oral Biol. Craniofac. Res. 6 (2) (2016) 153–159, https://doi.org/10.1016/j.jobcr.2015.12.002. Elsevier B.V. [9] E. Akyilmaz, E. Yorganci, E. Asav, Do copper ions activate tyrosinase enzyme? A biosensor model for the solution, Bioelectrochemistry 78 (2) (2010) 155–160, https://doi. org/10.1016/j.bioelechem.2009.09.007. [10] V. Venugopal, Biosensors in fish production and quality control, Biosens. Bioelectron. 17 (3) (2002) 147–157, https://doi.org/10.1016/S0956-5663(01)00180-4. [11] J. Wang, Electrochemical glucose biosensors, Chem. Rev. 108 (2) (2008) 814–825, https://doi.org/10.1021/cr068123a. [12] A. Kawamura, T. Miyata, Biosensors, in: Biomaterials Nanoarchitectonics, Elsevier Inc, 2016, pp. 157–176. [13] H.Y.M.R. Lee, Biosensors, in: J.S. Wilson (Ed.), Sensor Technology Handbook, Newnes, 2005, pp. 161–180.

66

Functionalized Nanomaterial-Based Electrochemical Sensors

[14] S.N. Sawant, Development of biosensors from biopolymer composites, in: Biopolymer Composites in Electronics, Elsevier Inc, 2017, pp. 353–383. [15] N.K. Sharma, A. Nain, K. Singh, N. Rani, A. Singal, Impedimetric sensors: principles, applications and recent trends, Int. J. Innov. Technol. Explor. Eng. 8 (10) (2019) 4015– 4025, https://doi.org/10.35940/ijitee.J9806.0881019. [16] M. Zhaleh, et al., In vitro and in vivo evaluation of cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound healing properties of gold nanoparticles produced via a green chemistry synthesis using Gundelia tournefortii L. as a capping, Appl. Organomet. Chem. 33 (9) (2019), https://doi.org/10.1002/aoc.5015, e5015. [17] M.R. Green, J. Sambrook, The Hanahan method for preparation and transformation of competent Escherichia coli: high-efficiency transformation, Cold Spring Harb. Protoc. (2018), https://doi.org/10.1101/PDB.PROT101188. pdb.prot101188. [18] R. Mukhopadhyay, V.V. Sumbayev, M. Lorentzen, J. Kjems, P.A. Andreasen, F. Besenbacher, Cantilever sensor for nanomechanical detection of specific protein conformations, Nano Lett. 5 (12) (2005) 2385–2388, https://doi.org/10.1021/nl051449z. [19] J. Wang, DNA biosensors based on peptide nucleic acid (PNA) recognition layers. A review, Biosens. Bioelectron. 13 (7–8) (1998) 757–762, https://doi.org/10.1016/ S0956-5663(98)00039-6. [20] R.J. Leatherbarrow, P.R. Edwards, Analysis of molecular recognition using optical biosensors, Curr. Opin. Chem. Biol. 3 (5) (1999) 544–547, https://doi.org/10.1016/S13675931(99)00006-X. Current Biology Ltd. [21] Z. Tüylek, Biyosensörler ve Nanoteknolojik Etkileşim, Bitlis Eren Üniv. Fen Bilim. Derg. 6 (2) (2017) 71–80, https://doi.org/10.17798/bitlisfen.299340. [22] L.D. Watson, P. Maynard, D.C. Cullen, R.S. Sethi, J. Brettle, C.R. Lowe, A microelectronic conductimetric biosensor, Top. Catal. 3 (2) (1987) 101–115, https://doi. org/10.1016/S0265-928X(87)80003-2. [23] P. Garg, A. Jamwal, D. Kumar, K.K. Sadasivuni, C.M. Hussain, P. Gupta, Advance research progresses in aluminium matrixcomposites: manufacturing & applications, J. Mater. Res. Technol. 8 (5) (2019) 4924–4939, https://doi.org/10.1016/j.jmrt.2019.06.028. Elsevier Editora Ltda. [24] Handbook of Functionalized Nanomaterials for Industrial Applications, Elsevier, 2020. [25] Handbook of Nanomaterials for Manufacturing Applications, Elsevier, 2020. [26] M.L. Tebaldi, R.M. Belardi, S.R. Montoro, Polymers with nano-encapsulated functional polymers: encapsulated phase change materials. encapsulated phase change materials, in: Design and Applications of Nanostructured Polymer Blends and Nanocomposite Systems, Elsevier Inc, 2016, pp. 155–169. [27] Nanomaterials definition matters, Nat. Nanotechnol. 143 (14) (2019), https://doi. org/10.1038/s41565-019-0412-3. 193-193. [28] M. Miernicki, T. Hofmann, I. Eisenberger, F. von der Kammer, A. Praetorius, Legal and practical challenges in classifying nanomaterials according to regulatory definitions, Nat. Nanotechnol. 14 (3) (2019) 208–216, https://doi.org/10.1038/s41565-019-0396-z. Nature Publishing Group. [29] J.L. Arlett, E.B. Myers, M.L. Roukes, Comparative advantages of mechanical biosensors, Nat. Nanotechnol. 6 (4) (2011) 203–215, https://doi.org/10.1038/nnano.2011.44. Nature Publishing Group. [30] Y. Pan, et  al., Electrochemical immunosensor detection of urinary lactoferrin in clinical samples for urinary tract infection diagnosis, Biosens. Bioelectron. 26 (2) (2010) 649–654, https://doi.org/10.1016/j.bios.2010.07.002.

Biofunctionalization of functionalized nanomaterials

67

[31] R. Chenthattil, J.G. Manjunatha, D.K. Ravishankar, S. Fattepur, G. Siddaraju, L. Nanjundaswamy, Validated electrochemical method for simultaneous resolution of tyrosine, uric acid, and ascorbic acid at polymer modified nano-composite paste electrode, Surf. Eng. Appl. Electrochem. 56 (4) (2020) 415–426, https://doi.org/10.3103/ S1068375520040134. [32] R. Keçili, S. Büyüktiryaki, C.M. Hussain, Membrane applications of nanomaterials, in: Handbook of Nanomaterials in Analytical Chemistry: Modern Trends in Analysis, Elsevier, 2019, pp. 159–182. [33] N. Hareesha, J.G. Manjunatha, A simple and low-cost poly (DL-phenylalanine) modified carbon sensor for the improved electrochemical analysis of riboflavin, J. Sci. Adv. Mater. Devices 5 (4) (2020) 502–511, https://doi.org/10.1016/j.jsamd.2020.08.005. [34] E.S. D’Souza, J.G. Manjunatha, C. Raril, G. Tigari, P.A. Pushpanjali, Polymer modified carbon paste electrode as a sensitive sensor for the electrochemical determination of riboflavin and its application in pharmaceutical and biological samples, Anal. Bioanal. Chem. Res. 7 (4) (2020) 461–472, https://doi.org/10.22036/ABCR.2020.214882.1445. [35] N. Hareesha, J.G.G. Manjunatha, C. Raril, G. Tigari, Design of novel surfactant modified carbon nanotube paste electrochemical sensor for the sensitive investigation of tyrosine as a pharmaceutical drug, Adv. Pharm. Bull. 9 (1) (2019) 132–137, https://doi.org/10.15171/ apb.2019.016. [36] J.G. Manjunatha, Fabrication of efficient and selective modified graphene paste sensor for the determination of catechol and hydroquinone, Surfaces 3 (3) (2020) 473–483, https://doi.org/10.3390/surfaces3030034. [37] J.G. Manjunatha, Poly (adenine) modified graphene-based voltammetric sensor for the electrochemical determination of catechol, hydroquinone and resorcinol, Open Chem. Eng. J. 14 (1) (2020) 52–62, https://doi.org/10.2174/1874123102014010052. [38] C.M. Hussain, Handbook of Nanomaterials for Industrial Applications, Elsevier, 2018. [39] C. Raril, et al., Surfactant immobilized electrochemical sensor for the detection of indigotine, Anal. Bioanal. Electrochem. (2018). (Online). Available from: www.abechem.com. (Accessed 24 December 2020). [40] P.A. Pushpanjali, J.G. Manjunatha, Development of polymer modified electrochemical sensor for the determination of alizarin carmine in the presence of tartrazine, Electroanalysis 32 (11) (2020) 2474–2480, https://doi.org/10.1002/elan.202060181. [41] N.S. Prinith, J.G. Manjunatha, R. Chenthattil, Magiran | Electrocatalytic analysis of dopamine, uric acid and ascorbic acid at poly(adenine) modified carbon nanotube paste electrode: a cyclic voltammetric study, Anal. Bioanal. Electrochem. 11 (6) (2019) 742–756. (Online). Available from: https://www.magiran.com/paper/1993830/?lang=en. (Accessed 24 December 2020). [42] N. Hareesha, J.G. Manjunatha, Fast and enhanced electrochemical sensing of dopamine at cost-effective poly(DL-phenylalanine) based graphite electrode, J. Electroanal. Chem. 878 (2020) 114533, https://doi.org/10.1016/j.jelechem.2020.114533. [43] P.I. Dolez, J. Mlynarek, Smart materials for personal protective equipment: tendencies and recent developments, in: Smart Textiles and Their Applications, Elsevier Inc, 2016, pp. 497–517. [44] B.M. Amrutha, J.G. Manjunatha, A.S. Bhatt, C. Raril, P.A. Pushpanjali, Electrochemical sensor for the determination of Alizarin Red-S at non-ionic surfactant modified carbon nanotube paste electrode, Phys. Chem. Res. 7 (3) (2019) 523–533, https://doi. org/10.22036/pcr.2019.185875.1636.

68

Functionalized Nanomaterial-Based Electrochemical Sensors

[45] N. Hareesha, J.G. Manjunatha, C. Raril, G. Tigari, Sensitive and selective electrochemical resolution of tyrosine with ascorbic acid through the development of electropolymerized alizarin sodium sulfonate modified carbon nanotube paste electrodes, ChemistrySelect 4 (15) (2019) 4559–4567, https://doi.org/10.1002/slct.201900794. [46] M.M. Charithra, J.G.G. Manjunatha, C. Raril, Surfactant modified graphite paste electrode as an electrochemical sensor for the enhanced voltammetric detection of estriol with dopamine and uric acid, Adv. Pharm. Bull. 10 (2) (2020) 247–253, https://doi. org/10.34172/apb.2020.029. [47] A. Ravindran, P. Chandran, S.S. Khan, Biofunctionalized silver nanoparticles: advances and prospects, Colloids Surf. B Biointerfaces 105 (2013) 342–352, https://doi. org/10.1016/j.colsurfb.2012.07.036. Elsevier. [48] I. Brigger, C. Dubernet, P. Couvreur, Nanoparticles in cancer therapy and diagnosis, Adv. Drug Deliv. Rev. 54 (5) (2002) 631–651, https://doi.org/10.1016/S0169-409X(02)00044-3. [49] B. Bonnemain, Superparamagnetic agents in magnetic resonance imaging: physicochemical characteristics and clinical applications. A review, J. Drug Target. 6 (3) (1998) 167–174, https://doi.org/10.3109/10611869808997890. Harwood Academic Publishers GmbH. [50] C. Xu, Z. Yuan, N. Kohler, J. Kim, M.A. Chung, S. Sun, FePt nanoparticles as an Fe reservoir for controlled Fe release and tumor inhibition, J. Am. Chem. Soc. 131 (42) (2009) 15346–15351, https://doi.org/10.1021/ja905938a. [51] H. Rui, R. Xing, Z. Xu, Y. Hou, S. Goo, S. Sun, Synthesis, functionalization, and biomedical applications of multifunctional magnetic nanoparticles, Adv. Mater. 22 (25) (2010) 2729–2742, https://doi.org/10.1002/adma.201000260. John Wiley & Sons, Ltd. [52] S. Eris, Z. Daşdelen, F. Sen, Investigation of electrocatalytic activity and stability of Pt@F-VC catalyst prepared by in-situ synthesis for methanol electrooxidation, Int. J. Hydrogen Energy 43 (1) (2018) 385–390, https://doi.org/10.1016/j.ijhydene.2017.11.063. [53] J.R. Stetter, W.R. Penrose, S. Yao, Sensors, chemical sensors, electrochemical sensors, and ECS, J. Electrochem. Soc. 150 (2) (2003) S11, https://doi.org/10.1149/1.1539051. [54] N. Ronkainen, S. Okon, Nanomaterial-based electrochemical immunosensors for clinically significant biomarkers, Materials (Basel) 7 (6) (2014) 4669–4709, https://doi. org/10.3390/ma7064669. [55] İ. Polatoğlu, Elektrokimyasal Biyosensörler için Karbon Pasta Elektrot Tasarımı ve Karakterizasyonu, Süleyman Demirel Üniv. Fen Bilim. Enst. Derg. 22 (2018) 141–148. [56] R.A. Hassan, L.Y. Heng, L.L. Tan, Novel DNA biosensor for direct determination of carrageenan, Sci. Rep. 9 (1) (2019) 1–9, https://doi.org/10.1038/s41598-019-42757-y. [57] C. Gao, Z. Guo, J.H. Liu, X.J. Huang, The new age of carbon nanotubes: an updated review of functionalized carbon nanotubes in electrochemical sensors, Nanoscale 4 (6) (2012) 1948–1963, https://doi.org/10.1039/c2nr11757f. [58] C. Shan, H. Yang, D. Han, Q. Zhang, A. Ivaska, L. Niu, Graphene/AuNPs/chitosan nanocomposites film for glucose biosensing, Biosens. Bioelectron. 25 (5) (2010) 1070–1074, https://doi.org/10.1016/j.bios.2009.09.024. [59] B.Y. Wu, et  al., Amperometric glucose biosensor based on layer-by-layer assembly of multilayer films composed of chitosan, gold nanoparticles and glucose oxidase modified Pt electrode, Biosens. Bioelectron. 22 (6) (2007) 838–844, https://doi.org/10.1016/j. bios.2006.03.009. [60] A.T. Lawal, Progress in utilisation of graphene for electrochemical biosensors, Biosens. Bioelectron. 106 (2018) 149–178, https://doi.org/10.1016/j.bios.2018.01.030. Elsevier Ltd. [61] A. Sánchez, A. Villalonga, G. Martínez-García, C. Parrado, R. Villalonga, Dendrimers as soft nanomaterials for electrochemical immunosensors, Nanomaterials 9 (12) (2019), https://doi.org/10.3390/nano9121745. MDPI AG.

Biofunctionalization of functionalized nanomaterials

69

[62] J.I. Anzai, Recent progress in electrochemical biosensors based on phenylboronic acid and derivatives, Mater. Sci. Eng. C 67 (2016) 737–746, https://doi.org/10.1016/j. msec.2016.05.079. Elsevier Ltd. [63] Y. Yang, X. Yang, Y. Yang, Q. Yuan, Aptamer-functionalized carbon nanomaterials electrochemical sensors for detecting cancer relevant biomolecules, Carbon 129 (2018) 380– 395, https://doi.org/10.1016/j.carbon.2017.12.013. Elsevier Ltd. [64] X. Chu, X. Fu, K. Chen, G.L. Shen, R.Q. Yu, An electrochemical stripping metalloimmunoassay based on silver-enhanced gold nanoparticle label, Biosens. Bioelectron. 20 (9) (2005) 1805–1812, https://doi.org/10.1016/j.bios.2004.07.012. [65] M. Musameh, J. Wang, A. Merkoci, Y. Lin, Low-potential stable NADH detection at carbon-nanotube-modified glassy carbon electrodes, Electrochem. Commun. 4 (10) ­ (2002) 743–746, https://doi.org/10.1016/S1388-2481(02)00451-4. [66] M. Dequaire, C. Degrand, B. Limoges, An electrochemical metalloimmunoassay based on a colloidal gold label, Anal. Chem. 72 (22) (2000) 5521–5528, https://doi.org/10.1021/ ac000781m. [67] C.J. Sunderland, M. Steiert, J.E. Talmadge, A.M. Derfus, S.E. Barry, Targeted nanoparticles for detecting and treating cancer, Drug Dev. Res. 67 (1) (2006) 70–93, https://doi. org/10.1002/ddr.20069.

This page intentionally left blank

Section C Functionalized carbon nanomaterial-based electrochemical sensors

This page intentionally left blank

Functionalized carbon nanomaterials in electrochemical detection

5

Sankararao Mutyalaa, P. Hari Krishna Charanb, Rajendran Rajaramc, and K. Naga Mahesha a Nanosol Energy Pvt Ltd, Hyderabad, Telangana, India, bDepartment of Chemistry, Aditya Institute of Technology and Management, Srikakulam, Andhra Pradesh, India, c Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, India

5.1 Introduction 5.1.1 General overview Carbon is one of the notable elements and has been described as the key element for living substances [1–3]. It has the ability to form a bond itself to form oligomers and polymers that allows carbon to play a vital role in life processes. This property can also be utilized to generate the huge number of structures that make it such a key commodity elements; for example, the element that leads to the basis of the FischerTropsch process, used by Sasol to make fuels and chemicals. But its ability to form strong bonds to oxygen to generate CO2 and lead to a carbon sink also reveals the “dark side” of carbon. The control and understanding of the bonding properties of carbon thus become crucial if the chemistry of carbon is to be harnessed for the good of the world’s peoples. Carbon has four outer shell electrons that can be used for bonding and this determines the structural chemistry that is associated with the element. In the classical valence bond picture, these four electrons (called sp3 electrons) are used to form a four bonds to other atoms. In simplest case, when the bonds only occur between carbon atoms, CC bonds are formed and the classical structure of diamond is produced (Fig. 5.1A). However, carbon can form multiple bonds between elements that give carbon many of its unique features. In this way, carbon can also link to another carbon atom to give CC is observed in graphite (Fig. 5.1B) and CC bonds are found in acetylene (Fig. 5.1C). The chemical and physical properties associated with the CC, CC, and CC interactions are all different and the ability to controllably synthesize structures containing these units leads to an exploitation of the chemistry of carbon. This property to make all carbon-containing nanomaterials, in particular those containing networks of CC double bonds, has been one of the key events that have led to the preset nanotechnology revolution. The discovery of fullerene in 1985 [4,5] and the subsequent studies by Iijima [6] on carbon nanotubes in 1991 were key events Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00024-7 Copyright © 2022 Elsevier Ltd. All rights reserved.

74

Functionalized Nanomaterial-Based Electrochemical Sensors

(A)

(B)

(C)

Carbon atoms Van der Waals bonds

HC

CH

Covalent bonds

Fig. 5.1  Schematic representation of carbon allotropes (A) diamond, (B) graphite, and (C) acetylene.

that have spurred the study of nanostructures in general and nano‑carbon structures in particular. Through these discoveries the third allotrope of carbon, following from graphite and diamond, allotropes was recognized this allotrope is based on a bent sp2 hybridized carbon. These discoveries coincided with an effort to use miniaturized devices such as cell phones, computers, etc., and the progress of advanced microscopy and spectroscopy techniques to visualize these new structural and morphological features of these materials. On the other hand, result of these materials has been emergence in the field of nanotechnology. The general form of oligomerized/polymerized carbon is soot and it was generated by thermal reactions of carbonaceous materials, produced an amorphous structure with little long-range order. But, by controlled decomposition of carbon-containing reactants under appropriate conditions it has been possible to make these carbons with long-range order. The structure morphology, such as shape, length and diameter of these carbon materials, is tuned by control of the experimental conditions of the carbon products at the nano level and this has generated a wide range of different shaped carbon nanomaterials. The synthetic approach is based on templating and self-assembly principles. The remarkable properties of nanocarbons include i. Carbon is a light element and structures are made from carbon tend to be lightweight. ii. Carbon in tabular form is considered the strongest material synthesized to date with a finite Young’s modulus [7]. iii. Carbon materials behaved as conductor, semiconductor or insulator and this tendency solely depends on the nature of carbon bonding. iv. Carbon in the form of diamond or graphene is the hardest material known. v. The optical studies of carbon have shown absorbances of 0.98–0.99 over a wide range of wavelengths, making them a near-perfect black body. vi. The thermal conductivity of carbon is variable in 0D, 1D, and 2D carbon materials. vii. The surface of carbon materials can be chemically modified (functionalized) leading to a new generation of reagents that can be used in a series of applications including energy, sensors, medical, fields, etc.

In particular, development in low-dimensional carbon nanomaterials, such as 0D fullerenes, 1D carbon nanotubes (CNTs), 2D graphene, etc., have further boosted the

Functionalized carbon nanomaterials in electrochemical detection

75

research for high performance and active materials for electrocatalysis and biosensor applications. In comparison with traditional carbon supports, nanostructured materials have several unique nanometer-sized effects that can add attractive electrochemical features to the resulting hybrid materials [8–11].

5.1.2 Carbon nanotubes (CNTs) and carbon nanofibers (CNFs) Carbon can form CNTs and CNFs in which the diameters typically range from 1 to 100 nm while the lengths can be typically around 10 nm to a few cm. Further, typically represented as a material showing good alignment, CNTs and CNFs are generally synthesized with an appearance more like “cooked spaghetti,” made of interwoven strands of carbon. It is also possible to make carbon tubes that have Y- and T-junctions. The difference between fibers and tubes relates to whether they are filled or hollow, but many variations of the filled and hollow tubes exist. Thus, the carbon tube/fiber can be made of V-shaped cups stacked on top of each other, or flakes that generate a herringbone structure. Finally, the tubes can be partially layered in the tube hollow, generating a bamboo structure. The ability to visualize the structure of carbon at nano level has permitted the exploration of the synthesis and morphology of nanocarbons. Variations in the structural morphology must be related to the properties and uses of the tubes/fibers.

5.1.3 Functionalization of CNTs The plethora of CNTs applications requires them to be dispersible in solvents (polar or nonpolar) and to be compatible with polymer matrices. To achieve this, surface functionalization, especially for the outer wall of CNTs, is necessary. Functionalization modifies the physical and chemical properties of CNTs. CNTs functionalization can be achieved by both covalent or noncovalent interactions and indeed, reviews have summarized functionalization strategies for CNTs [12]. Most of the methods reported require the synthesis and reactions of carboxylated CNTs, followed by covalent attachment of other functional groups to the CNTs [13–17]. Dispersion of CNTs can be achieved by sonication. The dispersion produced can be very stable and the CNTs can remain in solution for weeks or months. Functionalization methods such as oxidation of the CNTs can create more active binding sites on CNT surface. For biological uses, CNTs can be functionalized by attaching biological molecules, such as lipids and proteins, to surfaces. The CNT/biomolecule materials can be used to mimic biological processes, such as protein adsorption, the binding of DNA and drug molecules, and the fixing of red blood cells. These reactions are very useful in medicine (and pharmaceutics), particularly in drug delivery systems.

5.1.4 Graphene 5.1.4.1 Graphene is a material with great potential Graphene is defined by the International Union for Pure and Applied Chemistry (IUPAC) as “a single carbon layer of graphite structure, describing its nature by analogy to a polycyclic aromatic hydrocarbon of quasi-infinite size.” Graphene is the name

76

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 5.2  Graphitic forms, graphene is a 2D building material of all other dimensionalities. It can be wrapped up into 0D buckyballs, rolled into 1D nanotubes, or stacked into graphite. Reproduced from K.I. Bolotin, K.J. Sikes, Z. Jiang, M. Klima, G. Fudenberg, J. Hone, P. Kim, H.L. Stormer, Solid State Commun. 146 (2008) 351.

given to a flat monolayer of carbon atoms tightly packed as a two-dimensional (2D) honeycomb lattice [18–22]. Graphene is the basic structural element of some carbon allotropes such as graphite, charcoal, carbon nanotubes, and fullerenes are showed in Fig. 5.2.

5.1.4.2 Properties of graphene An ideal sheet of graphene consists of a 2D honeycomb structure of carbon atoms in a single layer. The considered graphene structure cannot have more than 10 layers [23]. Graphite and graphene are sharing many similarities among them and a frequent expression is that graphene is just one layer of graphite. One of the simple and first methods to produce graphene is achieved through micromechanical cleavage [24,25]. By repeatedly exposing a piece of graphite to the mechanical stress of a piece of tape,

Functionalized carbon nanomaterials in electrochemical detection

77

the weaker bindings between planes are destroyed. After creating a sufficient number of flakes, the tape can be dissolved and graphene material is collected. However, if the graphene sheets are re-stacked on top of one another, the crystalline structure of graphite should not reappear. Because the size of graphene sheets can have a wide range of lateral sizes depending on the method that creates the nanomaterials [18]. Graphene material has remarkable properties such as high stiffness and breaking strength. The values measured correspond to Young’s modulus of E = 1.0 TPa and intrinsic strength of 130 GPa, which would suggest that graphene is the strongest material ever measured [26]. The most intriguing features of graphene are its exceptional electronic quality and transport properties of individual graphene crystallites. Due to its 2D nature, graphene is theoretically a zero-bandgap semiconductor with excellent room temperature electrical conductivity [27,28]. It is also reported that graphene has a very high thermal conductivity [29]. Moreover, the pronounced carrier mobility is well maintained at the highest electron or hole concentrations of up to 1013 cm− 2 in ambipolar field-effect devices which suggest a ballistic transport on graphene crystal lattice [25,30]. The exceptional electronic properties of graphene also refer to the unusual room temperature half-integer quantum Hall effect [19,31].

5.2 Functionalization of carbon materials 5.2.1 Need and importance of functionalization of carbon materials Carbon materials such as carbon nanotubes (CNTs), graphene, fullerenes, etc. need to be functionalized; their direct use leads to frequent aggregation and in-solubilization limits its applications. Therefore, functionalization is extremely necessary to tune the physico-chemical surface properties of carbon materials for desired performance. Many methodologies have been proposed to produce doped or functionalized carbon materials for electrochemical sensor applications [32–36].

5.2.2 Types of functionalization

78

Functionalized Nanomaterial-Based Electrochemical Sensors

5.2.2.1 Activation method Activation method is a very common method employed for activating carbon materials using chemical activating agents [37]. Carbons are derived from coconut shells [38], petroleum residues and other biomass. Carbons derived from the above precursors are activated using activating agents such as KOH, thus forming activated carbon (AC). These ACs have many applications from catalysts to electrode materials. The AC derived needs to be functionalized to improve its efficiency in sensing applications [37]; Lee et al. have synthesized AC from petroleum-pitch and functionalized it with polypyrrole-(T-ppy).

Functionalization of activated carbons Measured quantity (0.65 g) of AC was mixed with 0.13 g of SDS in 200 mL of distilled water and stirred at room temperature for 2 h to form AC suspension and further T-Ppy is added and mixed thoroughly in stirred condition at room temperature for 24 h. The formed precipitates were filtered and washed with ethanol several times and vacuum dried at 60°C for 24 h [37]. Polyaniline can also be used to functionalize AC, Vighnesha et al. have prepared polyaniline via oxidative polymerization process from tetrafluoroboric acid solution using potassium persulfate as an oxidant [38]. PANI is used to functionalize AC by a mechanical stirring process with appropriate wt% of PVDF and N-methyl pyrrolidone as a binder, followed by loading on current-collector steel.

5.2.2.2 Hydrothermal method Polymer-based graphene materials can be used to detect ammonia (NH3). Huang et al. [39] have used polyaniline-based reduced graphene oxide (PANI-rGO) electrode for the detection of ammonia. For the preparation of electrode, a GO paper was used and subjected to ultra-sonication in distilled water to obtain a single layer of GO. Further, aniline polymerized GO-MnO2 was prepared using KMnO4 (by direct reaction) followed by thermal annealing [40]. The whole material was used to fabricate electrodes via a standard microfabrication method. In another invention, a novel rGO-based TiO2 thin-film sensor was reported by Ye and Tai [41]. A similar method of ultrasonication has been used for the preparation of rGO-TiO2 composite with 1:96 ratio in a hydrothermally treated mixture of TIP, HCl, and DI water. Further, prepared rGO-TiO2 composite material was used to fabricate as microelectrode and tested for the detection of NH3.

5.2.2.3 Immobilization, direct and in situ methods Graphene-based biosensor electrodes are prepared using the facile method [42]. Hummers method is used to synthesize GO from graphite with NaOH [43]. The rGO was sonicated with Palladium acetate to form an rGO/Pd hybrid [44]. The composite was prepared using the immobilization method. The poly-dopamine is used as polymer for the formation of rGO-based hybrid composite (PDA-Lac-rGO).

Functionalized carbon nanomaterials in electrochemical detection

79

The ­immobilization method was employed for the self-polymerization of dopamine. Ul Hasan et al. [45] have prepared a glucose sensor using the immobilization method for GO. Pt wire has used an electrode where a GO sheet is coated on it [46] and the electrode is introduced with glucose oxidase (GOD) enzyme electrostatically. The fabricated glucose sensor was tested using Ag/AgCl as a reference electrode.

5.2.2.4 Direct method Polyethylenimine (PEI)-based GO biosensor has been fabricated by PEI-GO-based sensor uses a 3D carbon electrode. GO was synthesized using modified Hummers method and further biofunctionalized using PEI in a single reaction. Further, the biosensor ability has been induced by adding ferrocene carboxylic acid, after combing with a biosensing enzyme. Fig. 5.4A provides the schematic of the biosensor prepared by PEI-GO electrode. A similar method was used to prepare a glucose-based biosensing electrode with a GOD (glucose oxidase) enzyme solution [47].

5.2.2.5 Thermal annealing Graphene films are used in NO2-based gas sensors; the graphene film was grown on 4H SiC crystal under Ar atmosphere at 1700°C shown in Fig. 5.3. Further, the graphene surface is modified using laser photolithography to form a bar-shaped design and then the fabrication of a graphene-based sensor chip was used in a prototype device. This type of sensor is a platinum resistor as a heater, due to its minimum thermal inertia. The fabricated sensor is tested for thermal cycling and tested for NO2 gas adsorption [48].

5.2.2.6 Electrospinning method The electrospinning method has been employed to prepare functionalized carbon fibers using polypyrrole (Ppy) and polyacrylonitrile (PAN) [49]. The prepared composite material can be used in flexible supercapacitors. The electrode fabrication includes the electrodeposition of MnO2 followed by wrapping of conductive Ppy layer around carbon fibers. The prepared composite Ppy-MnO2-CFs will be sandwiched with PVA/H3PO4 as the membrane as well as an electrolyte solution between the electrodes. Further, PAN-functionalized CFs (APCFs) are prepared using electrospinning technology [50], as mentioned in Fig. 5.4B. The KOH chemical activation will be done to pristine PAN-CFs material at 600–1000°C under N2 atmosphere [37].

5.2.2.7 In situ method The carbon-based gas sensors use of ZnO-rGO-based hybrid material for NO2 applications [27,28]. Hummers method is used to prepare rGO from graphite flakes and ZnO nanoparticles are decorated in situ; hydrazine hydrate is used as a reducing agent for the synthesis of hybrid ZnO-rGO composites. Further to fabricate an electrode, the ZnO-rGO materials were suspended in DMF and coated on ceramic substrates and used as electrodes and tested for NO2 gas sensors.

Fig. 5.3  (A) Schematic illustration of 2D and 3D carbon-based biosensors, (B) graphene-based sensor chips above holder, (C) synthetic layout of rGO-TiO2 thin film. Reproduced from S. Hemanth, A. Halder, C. Caviglia, Q. Chi, S. Keller, 3D carbon microelectrodes with bio-functionalized graphene for electrochemical biosensing, Biosensors 8 (2018) 70–78; S. Novikov, N. Lebedeva, A. Satrapinski, J. Walden, V. Davydov, A. Lebedev, Graphene based sensor for environmental monitoring of NO2, Sens. Actuator B: Chem. 236 (2016) 1054–1060.

Fig. 5.4  (A) Schematic layout of synthesis of activated carbon-polypyrrole (AC-PPy) composites. (B) Synthetic scheme of porous polymer-based carbon fibers (PPCE) preparation process by electrospinning technique. (C) General synthetic layout for rGONF/Ni(OH)2 fabrication. (A) Reproduced from J.W. Lee, H.I. Lee, S.J. Park, Facile synthesis of petroleum-based activated carbons/tubular polypyrrole composites with enhanced electrochemical performance as supercapacitor electrode materials, Electrochim. Acta 263 (2018) 447–453; (B) Reproduced from Y.J. Heo, H.I. Lee, J.W. Lee, M. Park, K.Y. Rhee, S.J. Park, Optimization of the pore structure of PAN based carbon fibers for enhanced supercapacitor performances via electrospinning, Compos. B Eng. 161 (2019) 10–17; (C) Reproduced from C. Zhang, Q. Chen, H. Zhan, Supercapacitors based on reduced graphene oxide nanofibers supported Ni(OH)2 nanoplates with enhanced electrochemical performance, ACS Appl. Mater. Interfaces 8 (2016) 22977–22987.

82

Functionalized Nanomaterial-Based Electrochemical Sensors

5.3 Applications of functionalized carbon materials in electrochemical biosensors Because of its salient features like highly abundant, low cost, low dimensions, physical, chemical, and biological properties, carbon materials have gained a huge deal of attention in analytical science. Different allotropes of carbon including fullerene, nanotubes, graphene, carbon nanohorns, and carbon dots are proposed for their catalytic activities in various sectors including sensor, environmental, energy, etc. They are being tried as an alternative for high-cost, less abundant noble materials. The applications of carbonaceous materials in electrochemical sensors will be discussed in the following section.

5.3.1 Applications of modified electrodes in electrochemical biosensors Biosensors are devices that are used to provide quantitative/semiquantitative information using biological recognitions [51–53]. The biosensors are inevitable in various sectors of healthcare including healthcare monitoring, screening of diseases, pollution control, environmental monitoring, etc. [52–56]. Despite the availability of several biosensors, electrochemical biosensors are found superior due to their sensitivity, selectivity, and reliability. The miniaturization of these sensors will make them portable for on-field analysis. Since the electrodes can be a source/sink of electrons during the electrochemical measurements, they are the major cause of the remarkable advantages of these biosensors. Yet, the raw, conventional, bare electrodes are unable to respond against several analytes. They lack sensitivity, selectivity, etc. To alleviate these issues, the electrodes are modified with suitable electrocatalyst materials to bring the required properties on electrodes surface against the analytes where a thin film of a selected layer will be used to modify the electrode surface.

5.3.2 Carbon materials as modifiers Among the various modifiers including metal nanoparticles, enzymes, metal composites, polymers, carbonaceous materials are playing a crucial role in electrochemical (bio)sensor applications. The size of carbon nanomaterials ranges from 1 nm to 1 μm which is comparable with the analytes like proteins, DNA, and other important natural bio-barriers like ion channels and glomerular filtration barrier [57]. Because of its size and optical properties, carbon nanomaterials can act as nanocapsules or nanocarriers to load and deliver the drugs in biomedical applications. IR spectrum produces a strong characteristic absorption band at 750–1000 nm for the carbon materials like CNT and graphene which is helpful in -photoacoustic imaging and photothermal therapy [58,59]. The unique fluorescence properties of CNTs make them effective candidates in deep tissue fluorescence imaging [60–63]. Because of these properties, they have been tried for electrochemical sensor applications. The role of the carbonaceous materials as modifiers in electrochemical sensors will be as follows.

Functionalized carbon nanomaterials in electrochemical detection

83

5.3.3 Fullerene modified electrodes Fullerene or C60 is the first discovered carbon nanostructure. It possesses 60 carbon atoms which are arranged as icosahedral. It is a polyhedron having 12 pentagonal and 20 hexagonal structures [64]. It is widely used for sensor applications. The hollow sphere of fullerenes can be doped with metal ions like Gd and Tc which can be used in magnetic resonance imaging and nuclear medicine applications [65,66]. The C60 molecule can be used to bind with the biomaterial, oligodeoxynucleotide which is used in gene delivery vehicles to pass the cell membrane and nuclear membrane by which one can improve the efficacy of gene therapy [67–69]. In addition to the metal ions and DNA, C60 can also be used as a drug carrier [70,71]. In the case of electrochemical biosensors, fullerene has been identified as an electrochemically active material that can lose or gain electrons [72]. Owing to their attractive catalytic properties and stability, fullerenes are used as a catalyst materials in electrochemical sensors. Upon modification, the sensitivity and electrochemical activity of fullerenes can be improved. Metal nanoparticle-modified fullerenes can improve sensitivity. Functionalization of fullerenes with polar groups may induce the hydrophilic character of fullerene [73,74]. Black fullerene is known for its electrocatalytic activity which is applied for the detection of acetaminophen and guanine. Pd nanoparticle-decorated fullerenes are reported for the electrochemical determination of dopamine where it improved the sensitivity against the target analyte at lower overpotential (Fig. 5.5) [75,76].

Fig. 5.5  (A) Electrochemical detection of dopamine at various concentrations from 0 to 150 μM using differential pulse voltammetry at AC60/PdNPs composite modified SPCE in PBS, and (B) Its linear plot for Ipa vs. [DA] with the error bars. Reproduced from S. Palanisamy, B. Thirumalraj, S.M. Chen, M.A. Ali, F.M.A. Al-Hemaid, Palladium nanoparticles decorated on activated fullerene modified screen printed carbon electrode for enhanced electrochemical sensing of dopamine, J. Colloid Interface Sci. 448 (2015) 251–256.

84

Functionalized Nanomaterial-Based Electrochemical Sensors

5.3.4 Carbon nanotubes in electrochemical sensors Alagappan et al. developed the cholesterol oxidase immobilized Au nanoparticle functionalized MWCNT polypyrrole modified electrode for electrochemical detection of bioanalytes. This matrix can sense cholesterol with a sensitivity and limit of detection of 10.12 μA mM− 1 cm− 2 and 100 μM, respectively [77]. Further, it is revealed that the role of CNT is remarkable in enzymatic, nonenzymatic and immunosensors. An electrochemical immunosensor has been developed for the pregnancy marker, hCG using SWCNT-modified screen-printed carbon electrode (SPCE). This matrix was found successful towards the detection of hCG in the concentration range of 10–1000 pg/ mL where the limit of detection was observed as 5 pg/mL [78]. Further, biocomposite comprising SWCNT-antibody were also reported for the detection of cancer biomarkers where the anti-tPA antibody was immobilized on SWCNT modified GCE via 1-ethyl-3-(3 dimethylaminopropyl) carbodiimide hydrochloride (EDC)/N-hydroxysuccinimide coupling and it was used for the detection of the biomarker with the limit of 0.026 ng/mL [79]. In order to improve the efficiency of CNTs, they can be functionalized using suitable mediators. The cavities of CNTs can be used to entrap the foreign mediators. But, agglomeration limits the application of these modifier-incorporated CNTs. Hence, chemical functionalization of CNTs will be crucial which will adjust the properties of CNTs. The functionalization will be helpful to get better dispersion of CNTs [80–82]. In this way, carboxyl functionalized CNTs are reported for their electrochemical performances in sensors [83]. Further CNTs were functionalized using chitosan and cetyltrimethylammonium bromide and it is utilized for the nonenzymatic electrochemical determination of hydroxymethanesulfinate [84]. Very interestingly, CNTs are functionalized using other carbonaceous materials, fullerenes (Fig. 5.6). This combination was found successful in electrochemical sensors [85,86]. Furthermore, a nanocomposite consisting of SnO2, β-CD, and MWCNT was prepared and used for the detection of acetaminophen [87].

5.3.5 Graphene-based materials in the electrochemical sensor Beitollahi et al. proposed composite containing graphene and ethyl 2-(4-ferrocenyl [1, 2, 3] triazol-1-yl) acetate to detect methyl dopamine. The composite is able to detect the analyte in two different linear ranges like 0.4–30.0 μM and 30.0–500.0 μM where the limit of detection obtained was 0.08 μM [88]. Further, graphene-modified GCE and nanoporous Pt-Y alloy were developed to detect dopamine. Here, the linearity of the matrix ranges from 0.9 to 82 μM with a detection limit of 0.36 μM [89]. Both the composites are found selective toward their target analytes. In addition, a disposable electrochemical immnosensor has been developed using carboxylic group enriched graphene oxide (GO) for the detection of cancer biomarker, mucin1 (MUC1) using methylene blue [90]. In another work, a disposable electrode was modified using a hybrid of Nile blue, gold, and graphene nanowire and it was used for the detection of dopamine [91–95]. Further, Au nanoparticle incorporated reduced graphene oxide was also developed for the successful electrochemical determination of homocysteine [96]. Another research article reports that a carbon paste electrode was developed

Functionalized carbon nanomaterials in electrochemical detection

l/mA

y = 0.6893x + 0.0459 R2 = 0.9984

0

l/mA

16

0

l/mA

10

0

A 11 22 [Hydrazine] / mm

120

y = 0.1021x + 18.413 R2 = 0.999

l/mA

20

y = 0.4873x + 0.2199 R2 = 0.9989

C 0 10 20 [Hydroxylamine] / mm

0 80 l/mA

100

85

0

0

B 400 800 [Hydrazine] / mm y = 0.1452x + 12.976 R2 = 0.9987

D 0 100 200 300 [Hydroxylamine] / mm

50

Hydrazine

Hydroxylamine

1

0 0.05

0.35

0.65 E/V

0.95

1.25

Fig. 5.6  Simultaneous determination of hydrazine and hydroxylamine using C60-CNTs/IL/GCE. Reproduced from M. Mazloum-Ardakani, A. Khoshroo, L. Hosseinzadeh, Simultaneous determination of hydrazine and hydroxylamine based on fullerene-functionalized carbon nanotubes/ionic liquid nanocomposite, Sens. Actuators B Chem. 214 (2015) 132–137.

­using DNA, l-cysteine, and Fe3O4 that was employed for the detection of adenine and guanine [97]. Further, electrochemical detection of salbutamol was also carried out using graphene and PEDOT:PSS [98]. A composite having graphene and Cu centered metal–organic framework (MOF) has been fabricated for the effective simultaneous determination of hydroquinone and catechol [99–102]. A Dopamine sensor was reported using carbonized hybrid gold and graphene on screen-printed carbon electrodes (SPCE) [103]. Carbon nanohorns (CNHs) are other classes of carbon materials that are conical in shape. Their length and diameter are usually 40–50 nm and 2–5 nm, respectively. This material is similar to CNTs except in the case of a diameter which is higher in CNHs. The nanohorns are spherically arranged with good porosity and a high specific surface. Since they do not contain toxic metallic impurities, they are environmentally friendly [104]. Moreover, the CNHs are made up of GPH. Since they possess good electrical conductivity, they can be applied to sensors [105–107] and these are ­functionalized

86

Functionalized Nanomaterial-Based Electrochemical Sensors

using polar groups by oxidation. Due to this process, modification (either by adsorption or by immobilization) of the nanohorns using catalysts can be achieved. Using this technique, the CNH is functionalized using cetyltrimethylammoniumbromide that is identified as an effective electrocatalyst for the electrochemical estimation of Bisphenol A [108]. After functionalization, CNHs have been used for the detection of metals like Cd and Pb [109]. Electrochemical deposition of polyglycine on carbon nanohorns was proposed for the simultaneous electrochemical estimation of ascorbic acid, uric acid, and dopamine [110–113].

5.3.6 Role of carbon/graphene quantum dots in electrochemical biosensors Graphene quantum dots (GQDs) are one of the branches of carbon quantum dots (CQDs). They are usually crystalline [114]. Like other carbonaceous materials, they also possess multiple extraordinary properties. Among them, small size, stability, and biocompatibility, etc. make them an efficient tool for drug administration and other biomedical applications [114,115]. The electrochemical properties of these quantum dots depend on the carbon core, the choice of heteroatom, and the functional groups [116]. The functional groups containing oxygen like COOH, COC, OH, CHO, and OCH3 are very crucial during the electrochemical measurements. The position of the oxygen group also decides the catalytic property of the quantum dots. GQDs having oxygen functional groups at the surface exhibit more electrocatalytic activity when compared to the groups at edges [117,118]. A combination of GQD and ionic liquid exhibits its electrocatalytic properties toward the sensing of ascorbic acid, uric acid, and dopamine (Fig. 5.7). From the work, it is revealed that matrix is efficient for the detection of those analytes in terms of enhanced sensitivity, attaining limit of detection, etc. [119]. However, the research on quantum dots and carbon dots still needs improvement. There are several problems to address with them. Their size, crystalline nature, and photoluminescence properties require further investigation to understand the mechanism behind their catalytic properties [120].

5.3.7 Carbon nanofibers as electroactive materials in electrochemical sensors Carbon nanofibers (CNFs) are another class of carbonaceous materials that are produced from hydrocarbonated gases or carbon monoxide along with metals like Fe, Co, Ni, and their alloys. There are different methods like laser ablation, electrospinning, arc discharge, etc. for the synthesis of CNFs [121,122]. Unlike CNTs, CNFs do not have any vacant cavity and disposition. In recent days, fiber-like structures are pronounced more for their conducting properties which may be helpful in electrochemical sensors. Because of its catalytic features, a CNF-based sensor has been developed for the electrochemical detection of tramadol (Fig. 5.8). The developed electrochemical sensor is found successful in terms of sensitivity, attaining a lower limit of detection, etc. The sensor was able to produce precise results in urine samples [123].

9.00

6 µM

8.00

DA UA

Current (mA)

7.00 6.00

0.2 µM

5.00 400 µM

4.00

10 µM

AA

3.00 2.00

0.5 µM

25 µM

1.00 0.00 –0.4

–0.2

0

0.2

0.4

0.6

0.8

E vs Ag/AgCl (V) Fig. 5.7  Simultaneous determination of ascorbic acid, uric acid, and dopamine at graphene quantum dot/ionic liquid modified screen-printed carbon electrode using differential pulse voltammetric analysis. Reproduced from K. Kunpatee, S. Traipop, O. Chailapakul, S. Chuanuwatanakul, Simultaneous determination of ascorbic acid, dopamine, and uric acid using graphene quantum dots/ionic liquid modified screen-printed carbon electrode, Sens. Actuators B Chem. 314 (2020) 128059.

16

14

y = 0.0852x + 4.8484 R2 = 0.9949

14 12

l/µA

12 10

10 8

l/µA

6 4

8

y = 3.8153x + 0.8262 R2 = 0.9603

2 0

6

0

50 C/nM

100

4 2 0 –0.3

–0.1

0.1

0.3

0.5

0.7

0.9

E/V

Fig. 5.8  Concentration-dependent square wave voltammograms of tramadol using electrospun carbon nanofiber modified screen-printed carbon electrode and its corresponding linear fit. The concentration ranges between 0.1 and 100 nM. Reproduced from Z. Jahromi, E. Mirzaei, A. Savardashtaki, M. Afzali, Z. Afzali, A rapid and selective electrochemical sensor based on electrospun carbon nanofibers for tramadol detection, Microchem. J. 157 (2020) 104942.

88

Functionalized Nanomaterial-Based Electrochemical Sensors

Acknowledgment section and set as per style. Acknowledgment RR thanks Indian Institute of Technology Madras for institute Postdoctoral Fellowship (MM21R002).

References [1] N.J. Coville, S.D. Mhlanga, E.N. Nxumalo, A. Shaikjee, A review of shaped carbon nanomaterials: review article, S. Afr. J. Sci. 107 (2011) 1. [2] C.M. Hussain, Handbook of Nanomaterials for Industrial Applications, Elsevier, 2018. [3] C.M. Hussain, Handbook of Environmental Materials Management, Elsevier, 2019. [4] C.M. Hussain, Handbook of Functionalized Nanomaterials for Industrial Applications, Elsevier, 2020. [5] M.S. Dresselhaus, G. Dressalhaus, P.C. Eklund, Science of Fullerenes and Carbon Nanotubes, Academic Press, New York, 1996. [6] S. Iijima, Helical microtubules of graphitic carbon, Nature 354 (1991) 56. [7] J.P. Salvetat, G.A.D. Briggs, J.-M. Bonard, et  al., Elastic and shear moduli of ­single-walled carbon nanotube ropes, Phys. Rev. Lett. 82 (1999) 944. [8] D.S. Su, S. Perathoner, G. Centi, Nanocarbons for the development of advanced catalysts, Chem. Rev. 113 (2013) 5782. [9] D. Jariwala, V.K. Sangwan, L.J. Lauhon, T.J. Marks, M.C. Hersam, Carbon nanomaterials for electronics, optoelectronics, photovoltaics, and sensing, Chem. Soc. Rev. 42 (2013) 2824. [10] C.M. Hussain, Handbook of Manufacturing Applications of Nanomaterials, Elsevier, 2020. [11] C.M. Hussain, Handbook of Industrial Applications of Polymer Nanocomposites, Elsevier, 2020. [12] K. Balasubramanian, M. Burghard, Chemically functionalized carbon nanotubes, Small 1 (2) (2005) 180. [13] R. Taylor, Lecture Notes on Fullerene Chemistry: A Handbook For Chemists, Imperial College Press, London, 1999. [14] C.M. Hussain, Handbook of Nanomaterials for Sensing Applications, Elsevier, 2020. after 8. [15] J.G. Manjunatha, A new electrochemical sensor based on modified carbon ­nanotube-graphite mixture paste electrode for voltammetric determination of resorcinol, Asian J. Pharm. Clin. Res. 10 (2017) 295. After 9. [16] G. Tigari, J.G. Manjunatha, Optimized voltammetric experiment for the determination of phloroglucinol at surfactant modified carbon nanotube paste electrode, Instrum. Exp. Tech. 63 (5) (2020) 750–757. [17] N.S. Prinith, J.G. Manjunatha, Polymethionine modified carbon nanotube sensor for sensitive and selective determination of L-tryptophan, J. Electrochem. Sci. Eng. 10 (2020) 305, https://doi.org/10.5599/jese.774. [18] A.K. Geim, K.S. Novoselov, The rise of graphene, Nat. Mater. 6 (2007) 183–191. [19] K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, M.I. Katsnelson, I.V. Grigorieva, S.V. Dubonos, A.A. Firsov, Two-dimensional gas of massless Dirac fermions in graphene, Nature 438 (2005) 197.

Functionalized carbon nanomaterials in electrochemical detection

89

[20] W. Tao, H. Frank, A. Hirsch, Covalent Inter-Synthetic-Carbon-Allotrope Hybrids, 2019, https://doi.org/10.1021/acs.accounts.9b00181. [21] C. Raril, J.G. Manjunatha, A simple approach for the electrochemical determination of vanillin at ionic surfactant modified graphene paste electrode, Microchem. J. 154 (2020) 104575, https://doi.org/10.1016/j.microc.2019.104575. [22] C. Raril, J.G. Manjunatha, A simple approach for the electrochemical determination of vanillin at ionic surfactant modified graphene paste electrode, Microchem. J. (2019) 104575, https://doi.org/10.1016/j.microc.2019.104575. [23] E. Fitzer, K.H. Kochling, H.P. Boehm, H. Marsh, Recommended terminology for the description of carbon as a solid, Pure Appl. Chem. 67 (1995) 473. [24] K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, Y. Zhang, S.V. Dubonos, I.V. Grigoriev, A.A. Firsov, Electric field effect in atomically thin carbon films, Science 306 (2004) 666. [25] K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, M.I. Katsnelson, I.V. Grigoriev, S.V. Dubonos, A.A. Firsov, Two-dimensional gas of massless Dirac fermions in graphene, Nature 438 (2005) 197. [26] C. Lee, X. Wei, J.W. Kysar, J. Hone, Measurement of the elastic properties and intrinsic strength of monolayer graphene, Science 321 (2008) 385. [27] J. Liu, Z. Yin, X. Cao, F. Zhao, A. Lin, L. Xie, Q. Fan, F. Boey, H. Zhang, W. Huang, Bulk heterojunction polymer memory devices with reduced graphene oxide as electrodes, ACS Nano 4 (2010) 3987. [28] J. Liu, Z. Lin, T. Liu, Z. Yin, X. Zhou, S. Chen, L. Xie, F. Boey, H. Zhang, W. Huang, Multilayer stacked low-temperature-reduced graphene oxide films: preparation, characterization, and application in polymer memory devices, Small 6 (2010) 1536. [29] A.A. Balandin, S. Ghosh, W. Bao, I. Calizo, D. Teweldebrhan, F. Miao, C.N. Lau, Superior thermal conductivity of single-layer graphene, Nano Lett. 8 (2008) 902. [30] K.I. Bolotin, K.J. Sikes, Z. Jiang, M. Klima, G. Fudenberg, J. Hone, P. Kim, H.L. Stormer, Ultrahigh electron mobility in suspended graphene, Solid State Commun. 146 (2008) 351. [31] K.S. Novoselov, Z. Jiang, Y. Zhang, S.V. Morozov, H.L. Stormer, U. Zeitler, J.C. Maan, G.S. Boebinger, P. Kim, A.K. Geim, Room-temperature quantum hall effect in graphene, Science 315 (2007) 1379. [32] J. Cheng, B. Wang, H.L. Xin, C. Kim, F. Nie, X. Li, G. Yang, H. Huang, Conformal coating of TiO2 nanorods on a 3-D CNT scaffold by using a CNT film as a nanoreactor: a free-standing and binder-free Li ion anode, J. Mater. Chem. A 2 (2014) 2701–2707. [33] J. Cheng, B. Wang, C.M. Park, Y. Wu, H. Huang, F. Nie, CNT@ Fe3O4@C coaxial nanocables: one-pot, additive-free synthesis and remarkable lithium storage behavior, Chem. A Eur. J. 19 (2013) 9866–9874. [34] S. Takenaka, H. Miyamoto, Y. Utsunomiya, H. Matsune, M. Kishida, Catalytic activity of highly durable Pt/CNT catalysts covered with hydrophobic silica layers for the oxygen reduction reaction in PEFCs, J. Phys. Chem. C 118 (2014) 774–783. [35] P.A. Pushpanjali, J.G. Manjunatha, M.T. Shreenivas, The electrochemical resolution of ciprofloxacin riboflavin and estriol using anionic surfactant and polymer‐modified carbon paste electrode, ChemistrySelect 4 (46) (2019) 13427–13433, https://doi. org/10.1002/slct.201903897. [36] J.G. Manjunatha, A novel poly (glycine) biosensor towards the detection of indigo carmine: a voltammetric study, J. Food Drug Anal. 26 (2018) 292.

90

Functionalized Nanomaterial-Based Electrochemical Sensors

[37] J.W. Lee, H.I. Lee, S.J. Park, Facile synthesis of petroleum-based activated carbons/ tubular polypyrrole composites with enhanced electrochemical performance as supercapacitor electrode materials, Electrochim. Acta 263 (2018) 447–453. [38] K.M. Vighnesha, Shruthi, Sandhya, D.N. Sangeetha, M. Selvakumar, Synthesis and characterization of activated carbon/conducting polymer composite electrode for supercapacitor applications, J. Mater. Sci. Mater. Electron. 29 (2018) 914–921. [39] X. Huang, N. Hu, Reduced graphene oxide–polyaniline hybrid: preparation, characterization and its applications for ammonia gas sensing, J. Mater. Chem. 22 (2012) 22488–22495. [40] M. Sathish, S. Mitani, T. Tomai, I. Honma, MnO2 assisted oxidative polymerization of aniline on graphene sheets: superior nanocomposite electrodes for electrochemical supercapacitors, J. Mater. Chem. A 21 (2011) 16216–16222. [41] Z. Ye, H. Tai, Excellent ammonia sensing performance of gas sensor based on graphene/titanium dioxide hybrid with improved morphology, Appl. Surf. Sci. 419 (2017) 84–90. [42] D.W. Li, L. Luo, P.F. Lv, Q.Q. Wang, K.Y. Lu, A.F. Wei, Q.F. Wei, Synthesis of polydopamine functionalized reduced graphene oxide-palladium nanocomposite for ­laccase-based biosensor, Bioinorg. Chem. Appl. (2016) 5360–5361. [43] X. Fan, W. Peng, Y. Li, X. Li, S. Wang, G. Zhang, F. Zhang, Deoxygenation of exfoliated graphite oxide under alkaline conditions: a green route to graphene preparation, Adv. Mater. 20 (2008) 4490–4493. [44] N. Karousis, G.-E. Tsotsou, F. Evangelista, P. Rudolf, N. Ragoussis, N. Tagmatarchis, Carbon nanotubes decorated with palladium nanoparticles: synthesis, characterization, and catalytic activity, J. Phys. Chem. C 112 (2008) 13463–13469. [45] K. Ul Hasan, M.H. Asif, O. Nur, M. Willander, Needle-type glucose sensor based on functionalized graphene, J. Biosens. Bioelectron. 3 (2012) 114–120. [46] A. Penicaud, C. Valles, Graphene Solutions, Centre National De La Recherche Scientifique CNRS, Paris, France, 2011. [47] S. Hemanth, A. Halder, C. Caviglia, Q. Chi, S. Keller, 3D carbon microelectrodes with bio-functionalized graphene for electrochemical biosensing, Biosensors 8 (2018) 70–78. [48] S. Novikov, N. Lebedeva, A. Satrapinski, J. Walden, V. Davydov, A. Lebedev, Graphene based sensor for environmental monitoring of NO2, Sens. Actuators B 236 (2016) 1054–1060. [49] J. Tao, N. Liu, W. Ma, L. Ding, L. Li, J. Su, Y. Gao, Solid-state high performance flexible supercapacitors based on polypyrrole-MnO2-carbon fiber hybrid structure, Sci. Rep. 3 (2017) 2286. [50] Y.J. Heo, H.I. Lee, J.W. Lee, M. Park, K.Y. Rhee, S.J. Park, Optimization of the pore structure of PAN based carbon fibers for enhanced supercapacitor performances via electrospinning, Compos. Part B Eng. 161 (2019) 10–17. [51] C. Feng, S. Dai, L. Wang, Optical aptasensors for quantitative detection of small biomolecules: a review, Biosens. Bioelectron. 59 (2014) 64–74. [52] J. Ali, J. Najeeb, M.A. Ali, M.F. Aslam, A. Raza, Biosensors: their fundamentals, designs, types and most recent impactful applications: a review, J. Biosens. Bioelectron. 8 (1) (2017) 1–9. [53] M. Gerard, A. Chaubey, B.D. Malhotra, Application of conducting polymers to biosensors, Biosens. Bioelectron. 17 (5) (2002) 345–359. [54] J. Wang, J. Wang, K. Rogers, Electrochemical Sensors for Environmental Monitoring: A Review of Recent Technology, Citeseer, 1995.

Functionalized carbon nanomaterials in electrochemical detection

91

[55] D.A. Polya, P.R. Lythgoe, F. Abou-Shakra, A.G. Gault, J.R. Brydie, J.G. Webster, K.L. Brown, M.K. Nimfopoulos, K.M. Michailidis, IC-ICP-MS and IC-ICP-HEX-MS determination of arsenic speciation in surface and groundwaters: preservation and analytical issues, Mineral. Mag. 67 (2) (2003) 247–261. [56] J.G. Manjunatha, A novel voltammetric method for the enhanced detection of the food additive tartrazine using an electrochemical sensor, Heliyon 4 (2018), e00986. [57] A. Ruggiero, C.H. Villa, E. Bander, D.A. Rey, M. Bergkvist, C.A. Batt, K. ManovaTodorova, W.M. Deen, D.A. Scheinberg, M.R. McDevitt, Paradoxical glomerular filtration of carbon nanotubes, Proc. Natl. Acad. Sci. U. S. A. 107 (2010) 12369–12374. [58] A. De La Zerda, C. Zavaleta, S. Keren, S. Vaithilingam, S. Bodapati, Z. Liu, J. Levi, B.R. Smith, T.-J. Ma, O. Oralkan, Carbon nanotubes as photoacoustic molecular imaging agents in living mice, Nat. Nanotechnol. 3 (9) (2008) 557–562. [59] J.T. Robinson, K. Welsher, S.M. Tabakman, S.P. Sherlock, H. Wang, R. Luong, H. Dai, High performance in vivo near-IR (> 1 Μm) imaging and photothermal cancer therapy with carbon nanotubes, Nano Res. 3 (11) (2010) 779–793. [60] K. Welsher, S.P. Sherlock, H. Dai, Deep-tissue anatomical imaging of mice using carbon nanotube fluorophores in the second near-infrared window, Proc. Natl. Acad. Sci. 108 (22) (2011) 8943–8948. [61] G. Hong, S. Diao, J. Chang, A.L. Antaris, C. Chen, B. Zhang, S. Zhao, D.N. Atochin, P.L. Huang, K.I. Andreasson, Through-skull fluorescence imaging of the brain in a new near-infrared window, Nat. Photonics 8 (9) (2014) 723–730. [62] G. Hong, J.C. Lee, J.T. Robinson, U. Raaz, L. Xie, N.F. Huang, J.P. Cooke, H. Dai, Multifunctional in  vivo vascular imaging using near-infrared II fluorescence, Nat. Med. 18 (12) (2012) 1841–1846. [63] C. Mangler, J.C. Meyer, Using electron beams to investigate carbonaceous materials, C. R. Phys. 15 (2–3) (2014) 241–257. [64] R.B. Mathur, B.P. Singh, S. Pande, Carbon Nanomaterials: Synthesis, Structure, Properties and Applications, CRC Press, 2016. [65] K.B. Ghiassi, M.M. Olmstead, A.L. Balch, Gadolinium-containing endohedral fullerenes: structures and function as magnetic resonance imaging (MRI) agents, Dalton Trans. 43 (20) (2014) 7346–7358. [66] L.R. Karam, M.G. Mitch, B.M. Coursey, Encapsulation of 99mTc within fullerenes a novel radionuclidic carrier, Appl. Radiat. Isot. 48 (6) (1997) 771–776. [67] A.S. Boutorine, M. Takasugi, C. Hélène, H. Tokuyama, H. Isobe, E. Nakamura, Fullerene–oligonucleotide conjugates: photoinduced sequence‐specific DNA cleavage, Angew. Chem. Int. Ed. Engl. 33 (23–24) (1995) 2462–2465. [68] H. Isobe, W. Nakanishi, N. Tomita, S. Jinno, H. Okayama, E. Nakamura, Nonviral gene delivery by tetraamino fullerene, Mol. Pharm. 3 (2) (2006) 124–134. [69] E. Nakamura, H. Isobe, Functionalized fullerenes in water. The first 10 years of their chemistry, biology, and nanoscience, Acc. Chem. Res. 36 (11) (2003) 807–815. [70] T.Y. Zakharian, A. Seryshev, B. Sitharaman, B.E. Gilbert, V. Knight, L.J. Wilson, A fullerene–paclitaxel chemotherapeutic: synthesis, characterization, and study of biological activity in tissue culture, J. Am. Chem. Soc. 127 (36) (2005) 12508–12509. [71] M. Suzuki, X. Lu, S. Sato, H. Nikawa, N. Mizorogi, Z. Slanina, T. Tsuchiya, S. Nagase, T. Akasaka, Where does the metal cation stay in Gd@ C 2 v (9)-C82? a single-crystal x-ray diffraction study, Inorg. Chem. 51 (9) (2012) 5270–5273. [72] N. Baig, M. Sajid, T.A. Saleh, Recent trends in nanomaterial-modified electrodes for electroanalytical applications, TrAC Trends Anal. Chem. 111 (2019) 47–61.

92

Functionalized Nanomaterial-Based Electrochemical Sensors

[73] S. Sutradhar, A. Patnaik, A new fullerene-C60–nanogold composite for non-enzymatic glucose sensing, Sens. Actuators B 241 (2017) 681–689. [74] A. Nimibofa, E.A. Newton, A.Y. Cyprain, W. Donbebe, Fullerenes: synthesis and applications, J. Mater. Sci. 7 (2018) 22–33. [75] F. Valentini, E. Ciambella, F. Cataldo, A. Calcaterra, L. Menegatti, M. Talamo, Fullerene black modified screen printed electrodes for the quantification of acetaminophen and guanine, Electroanalysis 29 (12) (2017) 2863–2872. [76] S. Palanisamy, B. Thirumalraj, S.M. Chen, M.A. Ali, F.M.A. Al-Hemaid, Palladium nanoparticles decorated on activated fullerene modified screen printed carbon electrode for enhanced electrochemical sensing of dopamine, J. Colloid Interface Sci. 448 (2015) 251–256. [77] M. Alagappan, S. Immanuel, R. Sivasubramanian, A. Kandaswamy, Development of cholesterol biosensor using Au nanoparticles decorated F-MWCNT covered with polypyrrole network, Arab. J. Chem. 13 (1) (2020) 2001–2010. [78] N.X. Viet, N.X. Hoan, Y. Takamura, Development of highly sensitive electrochemical immunosensor based on single-walled carbon nanotube modified screen-printed carbon electrode, Mater. Chem. Phys. 227 (2019) 123–129. [79] H.S. Nabiabad, K. Piri, F. Kafrashi, A. Afkhami, T. Madrakian, Fabrication of an immunosensor for early and ultrasensitive determination of human tissue plasminogen activator (TPA) in myocardial infarction and breast cancer patients, Anal. Bioanal. Chem. 410 (16) (2018) 3683–3691. [80] Q. Nie, W. Zhang, L. Wang, Z. Guo, C. Li, J. Yao, M. Li, D. Wu, L. Zhou, Sensitivity enhanced, stability improved ethanol gas sensor based on multi-wall carbon nanotubes functionalized with Pt-Pd nanoparticles, Sens. Actuators B 270 (2018) 140–148. [81] X. Ma, X. Tu, F. Gao, Y. Xie, X. Huang, C. Fernandez, F. Qu, G. Liu, L. Lu, Y. Yu, Hierarchical porous MXene/amino carbon nanotubes-based molecular imprinting sensor for highly sensitive and selective sensing of fisetin, Sens. Actuators B 309 (2020) 127815. [82] O.J. D’Souza, R.J. Mascarenhas, A.K. Satpati, L.V. Aiman, Z. Mekhalif, Electrocatalytic oxidation of L-tyrosine at carboxylic acid functionalized multi-walled carbon nanotubes modified carbon paste electrode, Ionics 22 (2016) 405–414. [83] V. Sudha, S.M.S. Kumar, R. Thangamuthu, Simultaneous electrochemical sensing of sulphite and nitrite on acid-functionalized multi-walled carbon nanotubes modified electrodes, J. Alloys Compd. 749 (2018) 990–999. [84] Z. Wu, F. Guo, L. Huang, L. Wang, Electrochemical nonenzymatic sensor based on cetyltrimethylammonium bromide and chitosan functionalized carbon nanotube modified glassy carbon electrode for the determination of hydroxymethanesulfinate in the presence of sulfite in foods, Food Chem. 259 (2018) 213–218. [85] M. Mazloum-Ardakani, A. Khoshroo, L. Hosseinzadeh, Simultaneous determination of hydrazine and hydroxylamine based on fullerene-functionalized carbon nanotubes/ ionic liquid nanocomposite, Sens. Actuators B 214 (2015) 132–137. [86] M. Mazloum-Ardakani, A. Khoshroo, L. Hosseinzadeh, Simultaneous determination of hydrazine and hydroxylamine based on fullerene-functionalized carbon nanotubes/ ionic liquid nanocomposite, Sens. Actuators B Chem. 124 (2015) 132, https://doi. org/10.1016/j.snb.2015.03.010. [87] R.K. Devi, G. Muthusankar, G. Gopu, L.J. Berchmans, A simple self-assembly fabrication of tin oxide nanoplates on multiwall carbon nanotubes for selective and sensitive electrochemical determination of antipyretic drug, Colloids Surf. A Physicochem. Eng. Asp. 598 (2020) 124825.

Functionalized carbon nanomaterials in electrochemical detection

93

[88] H. Beitollahi, K. Movlaee, M.R. Ganjali, P. Norouzi, R. Hosseinzadeh, Application of a nanostructured sensor based on graphene‐and ethyl 2‐(4‐ferrocenyl [1, 2,3] triazol‐1‐yl) acetate‐modified carbon paste electrode for determination of methyldopa in the presence of phenylephrine and guaifenesin, Appl. Organomet. Chem. 32 (4) (2018) 42–43. [89] X. Niu, Z. Mo, X. Yang, M. Sun, P. Zhao, Z. Li, M. Ouyang, Z. Liu, H. Gao, R. Guo, Advances in the use of functional composites of β-cyclodextrin in electrochemical sensors, Microchim. Acta 185 (7) (2018) 1–17. [90] S. Rauf, G.K. Mishra, J. Azhar, R.K. Mishra, K.Y. Goud, M.A.H. Nawaz, J.L. Marty, A. Hayat, Carboxylic group riched graphene oxide based disposable electrochemical immunosensor for cancer biomarker detection, Anal. Biochem. 545 (2018) 13–19. [91] H. Jin, C. Zhao, R. Gui, X. Gao, Z. Wang, Reduced graphene oxide/nile blue/gold nanoparticles complex-modified glassy carbon electrode used as a sensitive and ­label-free aptasensor for ratiometric electrochemical sensing of dopamine, Anal. Chim. Acta 1025 (2018) 154–162. [92] M.M. Charithra, J.G. Manjunatha, Surfactant modified graphite paste electrode as an electrochemical sensor for the enhanced voltammetric detection of estriol with dopamine and uric acid, Adv. Pharm. Bull. 10 (2020) 247–253, https://doi.org/10.34172/ apb.2020.029. [93] M.M. Charithra, J.G. Manjunatha, Enhanced voltammetric detection of paracetamol by using carbon nanotube modified electrode as an electrochemical sensor, J. Electrochem. Sci. Eng. 10 (1) (2020) 29–40, https://doi.org/10.5599/jese.717. [94] J.G. Manjunatha, M. Deraman, N.H. Basri, I.A. Talib, Selective detection of dopamine in the presence of uric acid using polymerized phthalo blue film modified carbon paste electrode, Adv. Mat. Res. 895 (2014) 447. [95] J.G. Manjunatha, M. Deraman, Graphene paste electrode modified with sodium dodecyl sulfate surfactant for the determination of dopamine, ascorbic acid and uric acid, Anal. Bioanal. Electrochem. 9 (2017) 198. [96] R. Rajaram, J. Mathiyarasu, An electrochemical sensor for homocysteine detection using gold nanoparticle incorporated reduced graphene oxide, Colloids Surf. B Biointerfaces 170 (2018) 109–114. [97] M. Arvand, M. Sanayeei, S. Hemmati, Label-free electrochemical DNA biosensor for guanine and adenine by Ds-DNA/poly (L-cysteine)/Fe3O4 nanoparticles-graphene oxide nanocomposite modified electrode, Biosens. Bioelectron. 102 (2018) 70–79. [98] D. Dechtrirat, B. Sookcharoenpinyo, P. Prajongtat, C. Sriprachuabwong, A. Sanguankiat, A. Tuantranont, S. Hannongbua, An electrochemical MIP sensor for selective detection of salbutamol based on a graphene/PEDOT: PSS modified screen printed carbon electrode, RSC Adv. 8 (1) (2018) 206–212. [99] J. Li, J. Xia, F. Zhang, Z. Wang, Q. Liu, An electrochemical sensor based on ­copper-based metal-organic frameworks-graphene composites for determination of dihydroxybenzene isomers in water, Talanta 181 (2018) 80–86. [100] J.G. Manjunatha, Fabrication of efficient and selective modified graphene paste sensor for the determination of catechol and hydroquinone, Surfaces 3 (3) (2020) 473–483, https://doi.org/10.3390/surfaces3030034. [101] J.G. Manjunatha, A promising enhanced polymer modified voltammetric sensor for the quantification of catechol and phloroglucinol, Anal. Bioanal. Electrochem. 12 (7) (2020) 893–903. [102] J.G. Manjunatha, Poly (adenine) modified graphene-based voltammetric sensor for the electrochemical determination of catechol, hydroquinone and resorcinol, Open Chem. Eng. J. (2020), https://doi.org/10.2174/1874123102014010052.

94

Functionalized Nanomaterial-Based Electrochemical Sensors

[103] P. Ekabutr, W. Klinkajon, P. Sangsanoh, O. Chailapakul, P. Niamlang, T. Khampieng, P. Supaphol, Electrospinning: a carbonized gold/graphene/PAN nanofiber for high performance biosensing, Anal. Methods 10 (8) (2018) 874–883. [104] N. Karousis, I. Suarez-Martinez, C.P. Ewels, N. Tagmatarchis, Structure, properties, functionalization, and applications of carbon nanohorns, Chem. Rev. 116 (8) (2016) 4850–4883. [105] S. Carli, L. Lambertini, E. Zucchini, F. Ciarpella, A. Scarpellini, M. Prato, E. Castagnola, L. Fadiga, D. Ricci, Single walled carbon nanohorns composite for neural sensing and stimulation, Sens. Actuators B 271 (2018) 280–288. [106] G. Zhu, M.N. Fiston, J. Qian, O.J. Kingsford, Highly sensitive electrochemical sensing of para-chloronitrobenzene using a carbon nanohorn–nanotube hybrid modified electrode, Anal. Methods 11 (8) (2019) 1125–1130. [107] A. Hasani, Approaches to graphene, carbon nanotube and carbon nanohorn, synthesis, properties and applications, Nanosci. Nanotechnol. Asia 10 (1) (2020) 4–11. [108] J. Zhang, X. Xu, Z. Chen, A highly sensitive electrochemical sensor for bisphenol A using cetyltrimethylammonium bromide functionalized carbon nanohorn modified electrode, Ionics (Kiel) 24 (7) (2018) 2123–2134. [109] Y. Yao, H. Wu, J. Ping, Simultaneous determination of Cd (II) and Pb (II) ions in honey and milk samples using a single-walled carbon nanohorns modified screen-printed electrochemical sensor, Food Chem. 274 (2019) 8–15. [110] G. Zhang, P. He, W. Feng, S. Ding, J. Chen, L. Li, H. He, S. Zhang, F. Dong, Carbon nanohorns/poly (glycine) modified glassy carbon electrode: preparation, characterization and simultaneous electrochemical determination of uric acid, dopamine and ascorbic acid, J. Electroanal. Chem. 760 (2016) 24–31. [111] J.G. Manjunatha, M. Deraman, N.H. Basri, I.A. Talib, Fabrication of poly (Solid Red A) modified carbon nano tube paste electrode and its application for simultaneous determination of epinephrine, uric acid and ascorbic acid, Arab. J. Chem. 11 (2018) 149. [112] J.G. Manjunatha, M. Deraman, N.H. Basri, Electrocatalytic detection of dopamine and uric acid at poly (basic blue b) modified carbon nanotube paste electrode, Asian J. Pharm. Clin. Res. 8 (2015) 48. [113] J.G. Manjunatha, Poly (nigrosine) modified electrochemical sensor for the determination of dopamine and uric acid: a cyclic voltammetric study, Int. J. ChemTech Res. 9 (2016) 136. [114] L. Wang, Y. Wang, T. Xu, H. Liao, C. Yao, Y. Liu, Z. Li, Z. Chen, D. Pan, L. Sun, Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties, Nat. Commun. 5 (1) (2014) 1–9. [115] P. Namdari, B. Negahdari, A. Eatemadi, Synthesis, properties and biomedical applications of carbon-based quantum dots: an updated review, Biomed. Pharmacother. 87 (2017) 209–222. [116] A. Ambrosi, C.K. Chua, A. Bonanni, M. Pumera, Electrochemistry of graphene and related materials, Chem. Rev. 114 (14) (2014) 7150–7188. [117] J. Feng, H. Dong, L. Yu, L. Dong, The optical and electronic properties of graphene quantum dots with oxygen-containing groups: a density functional theory study, J. Mater. Chem. C 5 (24) (2017) 5984–5993. [118] Y. Li, H. Shu, X. Niu, J. Wang, Electronic and optical properties of edge-functionalized graphene quantum dots and the underlying mechanism, J. Phys. Chem. C 119 (44) (2015) 24950–24957.

Functionalized carbon nanomaterials in electrochemical detection

95

[119] K. Kunpatee, S. Traipop, O. Chailapakul, S. Chuanuwatanakul, Simultaneous determination of ascorbic acid, dopamine, and uric acid using graphene quantum dots/ionic liquid modified screen-printed carbon electrode, Sens. Actuators B 314 (2020) 128059. [120] X. Li, M. Rui, J. Song, Z. Shen, H. Zeng, Carbon and graphene quantum dots for optoelectronic and energy devices: a review, Adv. Funct. Mater. 25 (31) (2015) 4929–4947. [121] B. Rezaei, M. Ghani, A.M. Shoushtari, M. Rabiee, Electrochemical biosensors based on nanofibres for cardiac biomarker detection: a comprehensive review, Biosens. Bioelectron. 78 (2016) 513–523. [122] A.V. Bounegru, C. Apetrei, Carbonaceous nanomaterials employed in the development of electrochemical sensors based on screen-printing technique—a review, Catalysts 10 (2020) 680. [123] Z. Jahromi, E. Mirzaei, A. Savardashtaki, M. Afzali, Z. Afzali, A rapid and selective electrochemical sensor based on electrospun carbon nanofibers for tramadol detection, Microchem. J. 157 (2020) 104942.

This page intentionally left blank

Functionalized carbon material-based electrochemical sensors for day-to-day applications

6

Vildan Erdurana,b, Muhammed Bekmezcia,b, Ramazan Bayat a,b, and Fatih Sena a Sen Research Group, Department of Biochemistry, Dumlupınar University, Kutahya, Turkey, bDepartment of Materials Science & Engineering, Faculty of Engineering, Dumlupınar University, Kütahya, Turkey

6.1 Introduction Carbon is one of the most important elements in the structure of most matter, with the sixth largest amount in the universe. Consists of carbon, graphene, carbon nanotubes reactions; broad and specific surface areas, electrochemical properties, and electrical conductivity of the thermal conductivity on good conditions, and they can be used in sensor technology in storage and energy has drawn interest in recent years to the science world because of promising properties [1–3]. All allotropic forms of carbons are used as important electrode materials, for example, graphite, glassy carbon, amorphous carbon, fullerenes, nanotubes, and doped diamond in modern electrochemistry. For example, graphite and amorphous carbons are used as anode in high energy density rechargeable Li-ion batteries, sensors, and fuel cells, porous carbon electrodes as nanoamorphous carbon composite electrodes as conductive agents, stable solid and high basic electrode materials as glassy carbon and doped diamonds. Carbon resilience gives a wide range of potential and temperature for a number of related electrolyte solutions, different exposure gasses and ions, very reactant/corrosive conditions, and conductive carbon products (e.g., amorphous) [1]. Nanomaterials, such as carbon nanotubes, graphene oxide, or metal nanoparticles, can be used as biosensors or electrocatalysts in electrochemical and biological fuel cells studies [4–7]. Carbon nanotubes have been one of the materials of interest in recent years. The carbon nanotubes are based on a period of 10  years since their discovery. Carbon nanotubes have very impressive properties. It is therefore used in many applications. Carbon nanotubes are used in electrochemical sensors as a possible content. The uses of carbon nanotubes as sensors and future opportunities are explored [8]. The detection mechanism (sensory organs) found in living things is being modeled by researchers to be obtained in a laboratory environment. Biosensors were obtained as a result of the conversion of a biological event in sensory systems to an electrical signal in a laboratory environment. Living things break down biological substances into their basic parts, enabling the perception of the stimuli that take place in the life process. Then, these parts and their relations are examined as a whole. Biosensor Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00017-X Copyright © 2022 Elsevier Ltd. All rights reserved.

98

Functionalized Nanomaterial-Based Electrochemical Sensors

structures are formed by combining the systems obtained as a result of these investigations (conversion of a biological event to an electrical signal) [9,10]. In nanomaterial-based studies, precision electrochemical biosensor applications are made to detect changes in electrochemical signals. These materials detect different concentrations of the intended molecules and their working products. In addition to detecting the situation with analytical principles, these sensors detect only targeted electrochemical signals thanks to functionalized nanomaterials. In this way, they reveal current situation in a sensitive and selective way [11]. Thanks to the progress in the electronics industries, biosensors are developing very rapidly. The fact that sensor technology covers areas of study such as chemistry, biology, materials science, engineering, and updating with new technologies in these disciplines has clearly contributed to the development of biosensors [12,13]. Biosensors are defined as the conversion of a biological event that takes place in the living body (depending on external factors) into an electrical signal. It is developed as a result of combining advanced electronic processing capabilities through the selectivity properties of biological molecules or systems by utilizing the knowledge gained from many branches of science such as physics, chemistry, biology, biochemistry, and engineering [14–16]. Biosensors are bioanalytic devices developed for use in many different industrial areas besides medicine and pharmacy. Biosensors enable the conversion of biological responses to different chemical properties used in biological analysis into optical, thermal, and electrical signals [17]. Biosensors have become small-sized structures as a result of the development of electronic circuits over time. Biosensors have been installed on chips thanks to nano-sized studies. However, the possession of biological structures in the electronic field and different responsiveness capabilities have been developed. When biosensor technology is examined it is seen to be influenced by nanotechnology [18]. Thanks to nanotechnology, their size is smaller, sensitive, long-lasting, and inexpensive. Biosensors will continue to evolve thanks to emerging technologies [19–22]. In general, the electrochemical biosensor relies on the reaction of enzymatic catalysis, which consumes or produces electrons. These types of enzymes are called redox enzymes. The substrate of this biosensor usually contains three electrodes, such as a counter, reference, and working type [23–27]. Biosensors are analytical technologies that selectively and irreversibly respond to the amount or activity of a chemical agent within any biological sample. A biosensor, schematically shown in Fig. 6.1, consists of biocomponents and physical components (transducer or inverter) [29,30]. Electrochemical sensors for public health monitoring, measurement, metabolite, disease screening, treatment, insulin, psychotherapy, clinical disease diagnosis, military applications, agricultural applications and veterinary drug, improvement, crime detection, processing and ecological applications such as pollution control can be obtained [31–38]. Electrochemical biosensors are divided into four different classes: amperometric biosensors, potentiometric biosensors, impedance biosensors, and voltammetric biosensors [39–42].

Functionalized carbon material-based electrochemical sensors

99

Fig. 6.1  Structure and operating principle of biosensors [28]. From B. Batra, V. Narwal, V. Kalra, M. Sharma, J.S. Rana, Folic acid biosensors: a review, Process Biochem. 92 (2020) 343–354, https://doi.org/10.1016/j.procbio.2020.01.025, Elsevier.

6.2 Electrochemical biosensors 6.2.1 Amperometric biosensors Concentrate-dependent current measurement by means of electrochemical electrodes coated with biologically active matter amperometric biosensors (Fig. 6.2) [42,44–46]. The operating principle of the biosensor mentioned depends on the quantity changes in the controlled current flow. There is a wide range of uses including selecting analyte centers, high-efficiency medical screening, quality control, problem finding and processing, and biological control [47,48]. The principle of operation of amperometric biosensors is that they provide electron transfer at a suitable potential to the potential domain of the immobilized enzyme. Providing different electrode surface and electron transfer applications is one of the ways to solve construction problems for amperometric biosensors. Modifications to electron transfer pathways may be used, for example, polymer chains hopping over carbon conductors [49]. Besides, high-performance Gluco sensor for detecting current released from human serum has facilitated the use of Ag-Au/RGO nanostructures as electrochemical biosensors in future studies [50].

6.2.2 Potentiometric biosensors Changes in ionic concentrations with ion-selective electrodes are calculated in such biosensors. Potentiometric biosensors’ biggest weakness is their susceptibility to ionic concentrations such as H+ and NH4+ [23,51–53]. The potential discrepancy between the potential electrode and the reference electrode can be calculated, and this value is commensurate with the substratum concentration (Fig. 6.3) [54–57].

100

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 6.2  Amperometric biosensors [43]. From N.P. Negi, T. Choephel, Biosensor: an approach towards a sustainable environment, in: M. Mohsin, R. Naz, A. Altaf (Eds.), Nanobiosensors for Agricultural, Medical and Environmental Application, Springer, Singapore, 2020, https://doi.org/10.1007/978-981-15-8346-9.

Using biocatalytic and bioaffinity-based biosensor plans, a number of potential biosensors have been developed. And that for biomedical research only a handful are relevant. The most positive is that the major metabolism ingredients, urea, and creatinine, are observed. A new category is made up of bioaffinite-based instruments that can be used for either immunoassay or genoanalysis. Any alternative biosensors that are suitable for true biomedical research are used [58]. With new generation materials such as potentiometric ion-selective electrodes and emerging new techniques, potentiometric bioalgae systems have been developed [59]. Features such as robustness, ease of use and cheap cost, which are considered unbeatable, are the reasons why Potentiometric sensors are preferred. Although it does not match the clinical range, a Potentiometric biosensor has been developed as a result of coating the Pt electrode with Nafion, which is intended for use in glucose

Functionalized carbon material-based electrochemical sensors

101

Fig. 6.3  Potentiometric biosensor [43]. From N.P. Negi, T. Choephel, Biosensor: an approach towards a sustainable environment, in: M. Mohsin, R. Naz, A. Altaf (Eds.), Nanobiosensors for Agricultural, Medical and Environmental Application, Springer, Singapore, 2020, https://doi. org/10.1007/978-981-15-8346-9.

determination. Another Potentiometric sensor was later developed for glucose determination using Aquivion, which showed similar properties instead of Nafion [60].

6.2.3 Impedance biosensors A sensitive indicator of a broad ranging physical and chemical properties is electrochemical impedance spectroscopy. An increasing trend toward the use of impedance biosensors (Fig. 6.4) is currently being observed. Impedance techniques were carried out to separate the invention of biosensors and study the reactions of enzymes, lactins, nucleic acids, receptors, and antibodies [61–64]. A lack of certain vitamins or substances in the body, such as vitamin B2 or dopamine, can cause damage or even cancer in the body. Professional determination devices are available for the determination of such substances. But with electrochemical techniques, simpler, faster applications can be made [65–68]. Benzene-1,3-diol, a phenolic organic compound, can lead to problems such as dermatitis. Electrochemical sensors can be used to detect this substance [69]. Impedance biosensors are a class of electrical biosensors that, due to low cost, simple miniaturization, and nonmarked service, demonstrate a potential for point of care and other applications. Using surface impedance modifications when a target molecule binds to an immobilized sample, unlabeled DNA and protein targets may be observed. The move to catch Affinity leads to problems shared by all biosensors without mark affinity, which are addressed along with others that are unique to impedance re-reading. Different pathways are addressed to alter impedance with target binding. We summarize crucial milestones and areas for future study of previous label-free impedance biosensors [70].

102

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 6.4  Structure of impedance biosensors [61]. From C. Fernández-Sánchez, C.J. McNeil, K. Rawson, Electrochemical impedance spectroscopy studies of polymer degradation: application to biosensor development, TrAC, Trends Anal. Chem. 24 (2005) 37–48, https://doi.org/10.1016/j.trac.2004.08.010.

6.2.4 Voltammetric biosensors This biosensor is constructed with a carbon glue electrode adapted with Hb (hemoglobin). This electrode type indicates the reversible oxidation or reduction procedure of Hb [71,72]. A voltammetric sensor can operate in linear or cyclic voltammetric modes. As a result, the relevant current and voltage will be different for each mode [73,74]. Electrochemical biosensors are one of the reasons why they are preferred in recent studies because they can be obtained at a low cost and also because their use is simple. MiRNA studies are of great interest due to the speed with which these sensors respond to the warning in use, their application, and their easy mass production [75]. Biosensors based on molecular printed polymers have also been developed in conjunction with a voltammetric transducer for histamine detection as a voltammetric biosensor application. The resulting sensor’s voltammetric signals differed successfully compared to the histamine signal, which is a highly successful method for histamine selection [76]. At the same time, in some studies, for example, for tyrosine detection, electrochemical sensor systems based on graphite‑carbon nanotube [77] electrodes modified by poly threonine have been developed [78–81]. In the same way, systems based on an ionic surfactant-modified graphene paste electrode have been developed for the determination of vanillin (VN) [82].

Functionalized carbon material-based electrochemical sensors

103

6.3 Supercapacitors In applications such as energy storage chips, implantable electronic systems, ­radio-free electric sensors and others, supercapacities have an important role to play. Mini supercondensers provide sandwiched, rolled, and digital interfaces for various electrode configurations [83–85]. Higher power density, longer service life, and cheapness are the tremendous advantages of superconductors. Electrodes need to show high ionic sorption potential at solid-liquid interfaces and fast charge transfer for industrial applications of the supercapacitor. For this reason, scientists have used different ­carbon-based materials (ACs, CFs, graphs, etc.) [86–89]. Graphene-based materials are of great interest in energy storage technology. Along with three-dimensional (3D) structures interpreted with graphene, the importance of devices used in energy storage is increasing. Aerogel structures created with graphene are increasingly used in the construction of supercapacitors [90].

6.4 Gas sensors Gas sensors are devices that help us understand the amount of gas in the environment and the natural state of its movement. Gas sensors reveal the amount of gas in the environment and the nature of the gas composition with electrical signals and can provide its change [91–93]. The parameters that should be considered when creating gas sensors are as follows: the type of gas that needs to be detected, its concentration, and the environment in which the gas is located. MWCNT gas adsorption occurs in the outer region where the gas molecule is connected to the sensor together with the van der Waals force. The electrical charge flow in the gas sensor differs from the binding of the molecule. With this differentiation, gas sensor resistance is determined to differ [94].

6.5 Wearable electronic devices A vast variety of lightweight and stretchable components, including interchangeable sensors or soft electrodes and circuitry, are available for use in various wearable devices. Wearable electronics have proved themselves to be very effective in the healthcare industry to track human wellbeing, activity, and heat treatment [95–97]. The wire is an electrode graphic pen, and minimal weight is a stretchable, durable, biologically recyclable substrate. This CNT-based instrument is used as a sensor for the tracking and diagnosis of respiratory diseases by repairing human skin [98]. They also fixed in a related sensor a temperature detective for the noncontact mode study of the human body’s temperature. This discovery opened the door for the use of CNT yarns for the production of a large variety of environmentally friendly, cheaper, lightweight, and wearable temperature and respiratory electronics [98]. The use of this pressure sensor in synthetic robotic skin was also tested for the detection of intensity

104

Functionalized Nanomaterial-Based Electrochemical Sensors

and pressure responses. Wearable sensors have since been created for the monitoring of human activity and the athletic exercises of athletes [99,100]. Textile wearables based on rGO offer a wide range of advantages in contrast with conventional methods. These conventional protocols are complicated and inappropriate for a number of functional applications. Later, a simple cheap technique was recorded for manufacturing doped wearables using an easy pad-dry approach. This technology allowed the development of conductive rGO e-textiles at an industrial production rate of approximately 150 min [101]. RGO-based e-textile electronic systems that were wearable had a durable softness, flexibility, and washability. The use of RGO improved the lightweight structure and tensile strength of cotton fabrics by increasing the overall stress percentage at the highest weight [102].

6.6 Piezoelectric sensors The theory of this type of sensor is that the vibrational frequency of the oscillating crystal is decreased by the adsorption of a foreign material on its surface. The crystal is sensitized by association or analysis. Piezoelectrical meters are used for metering, ammonia, nitrogen oxides, and some organophosphate compounds—carbon monoxide, sugars, hydrogen, methane, and sulfur dioxide. It is difficult to apply this approach to aqueous environments, that is, the conditions typical to biological systems [103,104]. Flexible stress sensors, which have received a lot of attention in recent years, are expected to have some characteristics. These features are high flexibility, repeatability, and sensitivity. The superior electrical properties and flexibility of carbon-based materials such as graphene, graphite, and CNT lead to the frequent use and interest of these materials. Flexible sensors in different forms can be prepared from these materials [105]. Conducting nanogenerator designs together with the usual textile production, developing a new generation of wearable electronic clothing and, moreover, artificial intelligence has become more and more interesting and used every day [106]. In low-power electronic devices, piezoelectric nanogenerators can be used to efficiently convert existing mechanical energy into electrical energy to adequately meet energy requirements [107]. In addition, in the production of next-generation materials such as piezoelectric structures, optical fiber sensors, and composites, structural health monitoring (SHM) for strain/temperature measurements is of little interest [108].

6.7 Conclusion In recent years, carbon material-based electrochemical sensors have become quite churn-free in everyday uses. These materials are user-friendly, cost-efficient, responsive and compact, since they are the subject of study. There are reasons to be used of a broad range in detecting chemical and bio-targets in amperometric

Functionalized carbon material-based electrochemical sensors

105

sensors, electrochemical sensors, and electrochemical equipments, including filters, and light electrochemical sensors. In this way, increased sensor diversity increases the importance of greater use in everyday life. Given these advances, due to their simplicity, sensitivity and precision, electrochemical methods are among the most promising science. Biosensors focused on extremely sensitive and sensitive nanomaterials paved the way for new early detection and diagnostic tools for the diagnosis of biomaterials associated with diseases. A wide variety of electrochemical sensors have been developed with advanced analytical capabilities due to the attractive properties of the nanomaterials. This direction offers knowledge about electrochemical sensor-based nanomaterials and shows their advantages in many significant biomedical applications and their successful use. This topic was built on the interface between chemistry and life science, nanomaterial synthesis, supramolecular chemistry, and regulated medicine. This is therefore the result of a multiplier analysis. The form and use of electrical biosensors in everyday life were described in this report. In this study, we tried to address the areas of use of carbon-based electrochemical biosensors in everyday life. Electrochemical biosensors, which have many applications, appear in everyday use as supercapacitors in early diagnosis and treatment of diseases, in wearable technology applications, in determining the amount of gas in systems, in energy storage systems.

References [1] M. Noked, A. Soffer, D. Aurbach, The electrochemistry of activated carbonaceous materials: past, present, and future, J. Solid State Electrochem. 15 (2011) 1563–1578, https:// doi.org/10.1007/s10008-011-1411-y. [2] D. Chen, L. Tang, J. Li, Graphene-based materials in electrochemistry, Chem. Soc. Rev. 39 (2010) 3157–3180, https://doi.org/10.1039/b923596e. [3] P.-C. Ma, J.-K. Kim, Carbon Nanotubes for Polymer Reinforcement, CRC Press, 2017, pp. 1–224. ISBN: 9781138073302. [4] H. Burhan, H. Ay, E. Kuyuldar, F. Sen, Monodisperse Pt-Co/GO anodes with varying Pt: Co ratios as highly active and stable electrocatalysts for methanol electrooxidation reaction, Sci. Rep. (2020), https://doi.org/10.1038/s41598-020-63247-6. [5] E. Kuyuldar, H. Burhan, A. Şavk, B. Güven, C. Özdemir, S. Şahin, A. Khan, F. Şen, Enhanced electrocatalytic activity and durability of PtRu nanoparticles decorated on rGO material for ethanol oxidation reaction, in: Carbon Nanostructures, Springer International Publishing, 2019, pp. 389–398, https://doi.org/10.1007/978-981-32-9057-0_16. [6] F. Şen, Mesoporous Materials in Biofuel Cells, Materials Research Foundations, Materials Research Forum LLC, 2019, pp. 157–172, https://doi.org/10.21741/9781644900079-7. [7] Use of Carbon-Nanotube Based Materials in Microbial Fuel Cells, 2019, pp. 151–176, https://doi.org/10.21741/9781644900116-7. [8] Q. Zhao, Z. Gan, Q. Zhuang, Electrochemical sensors based on carbon nanotubes, Electroanalysis 14 (2002) 1609–1613, https://doi.org/10.1002/elan.200290000. [9] N.J. Ronkainen, H.B. Halsall, W.R. Heineman, Electrochemical biosensors, Chem. Soc. Rev. 39 (2010) 1747–1763, https://doi.org/10.1039/b714449k. [10] Z. Tüylek, Biyosensörler ve Nanoteknolojik Etkileşim, 2017.

106

Functionalized Nanomaterial-Based Electrochemical Sensors

[11] C. Zhu, G. Yang, H. Li, D. Du, Y. Lin, Electrochemical sensors and biosensors based on nanomaterials and nanostructures, Anal. Chem. 87 (2015) 230–249, https://doi. org/10.1021/ac5039863. [12] M. Ruiz-Altisent, L. Ruiz-Garcia, G.P. Moreda, R. Lu, N. Hernandez-Sanchez, E.C. Correa, B. Diezma, B. Nicolaï, J. García-Ramos, Sensors for product characterization and quality of specialty crops-a review, Comput. Electron. Agric. 74 (2010) 176–194, https://doi.org/10.1016/j.compag.2010.07.002. [13] G. Korotcenkov, Gas Diffused Electrodes, 2013, https://doi.org/10.1007/978-1-4614-7165-3. [14] D. Grieshaber, R. MacKenzie, J. Vörös, E. Reimhult, Electrochemical biosensors—sensor principles and architectures, Sensors 8 (2008) 1400–1458, https://doi.org/10.3390/ s80314000. [15] B. Bohunicky, S.A. Mousa, Biosensors: the new wave in cancer diagnosis, Nanotechnol. Sci. Appl. 4 (2011) 1–10, https://doi.org/10.2147/NSA.S13465. [16] M.U. Ahmed, I. Saaem, P.C. Wu, A.S. Brown, Personalized diagnostics and biosensors: a review of the biology and technology needed for personalized medicine, Crit. Rev. Biotechnol. 34 (2014) 180–196, https://doi.org/10.3109/07388551.2013.778228. [17] T.G.M. Schalkhammer, Biosensors, in: Analytical Biotechnology, Birkhäuser Basel, Basel, 2002, pp. 167–219, https://doi.org/10.1007/978-3-0348-8101-2_5. [18] S. Palit, C.M. Hussain, Functionalization of nanomaterials for industrial applications: recent and future perspectives, in: Handbook of Functionalized Nanomaterials for Industrial Applications, Elsevier, 2020, pp. 3–14, https://doi.org/10.1016/ b978-0-12-816787-8.00001-6. [19] M. Alvarez, L.M. Lechuga, Microcantilever-based platforms as biosensing tools, Analyst 135 (2010) 827–836, https://doi.org/10.1039/b908503n. [20] S. Dhanekar, S. Jain, Porous silicon biosensor: current status, Biosens. Bioelectron. 41 (2013) 54–64, https://doi.org/10.1016/j.bios.2012.09.045. [21] K. Kerman, M. Saito, E. Tamiya, S. Yamamura, Y. Takamura, Nanomaterial-based electrochemical biosensors for medical applications, TrAC, Trends Anal. Chem. 27 (2008) 585–592, https://doi.org/10.1016/j.trac.2008.05.004. [22] A.P.F. Turner, Biosensors: sense and sensibility, Chem. Soc. Rev. 42 (2013) 3184–3196, https://doi.org/10.1039/c3cs35528d. [23] W.H. Scouten, J.H.T. Luong, R. Stephen Brown, Enzyme or protein immobilization techniques for applications in biosensor design, Trends Biotechnol. 13 (1995) 178–185, https://doi.org/10.1016/S0167-7799(00)88935-0. [24] C. Léger, S.J. Elliott, K.R. Hoke, L.J.C. Jeuken, A.K. Jones, F.A. Armstrong, Enzyme electrokinetics: using protein film voltammetry to investigate redox enzymes and their mechanisms, Biochemistry 42 (2003) 8653–8662, https://doi.org/10.1021/ bi034789c. [25] A. Chaubey, B.D. Malhotra, Mediated biosensors, Biosens. Bioelectron. 17 (2002) 441–456, https://doi.org/10.1016/S0956-5663(01)00313-X. [26] W.W. Zhao, J.J. Xu, H.Y. Chen, Photoelectrochemical enzymatic biosensors, Biosens. Bioelectron. 92 (2017) 294–304, https://doi.org/10.1016/j.bios.2016.11.009. [27] C. Léger, P. Bertrand, Direct electrochemistry of redox enzymes as a tool for mechanistic studies, Chem. Rev. 108 (2008) 2379–2438, https://doi.org/10.1021/cr0680742. [28] B. Batra, V. Narwal, V. Kalra, M. Sharma, J.S. Rana, Folic acid biosensors: a review, Process Biochem. 92 (2020) 343–354, https://doi.org/10.1016/j.procbio.2020.01.025. [29] S.M. Borisov, O.S. Wolfbeis, Optical biosensors, Chem. Rev. 108 (2008) 423–461, https://doi.org/10.1021/cr068105t.

Functionalized carbon material-based electrochemical sensors

107

[30] K. Narsaiah, S.N. Jha, R. Bhardwaj, R. Sharma, R. Kumar, Optical biosensors for food quality and safety assurance-a review, J. Food Sci. Technol. 49 (2012) 383–406, https:// doi.org/10.1007/s13197-011-0437-6. [31] L. Rassaei, F. Marken, M. Sillanpää, M. Amiri, C.M. Cirtiu, M. Sillanpää, Nanoparticles in electrochemical sensors for environmental monitoring, TrAC, Trends Anal. Chem. 30 (2011) 1704–1715, https://doi.org/10.1016/j.trac.2011.05.009. [32] M.I. Mead, O.A.M. Popoola, G.B. Stewart, P. Landshoff, M. Calleja, M. Hayes, J.J. Baldovi, M.W. McLeod, T.F. Hodgson, J. Dicks, A. Lewis, J. Cohen, R. Baron, J.R. Saffell, R.L. Jones, The use of electrochemical sensors for monitoring urban air quality in low-cost, high-density networks, Atmos. Environ. 70 (2013) 186–203, https://doi. org/10.1016/j.atmosenv.2012.11.060. [33] B. Fleet, H. Gunasingham, Electrochemical sensors for monitoring environmental pollutants, Talanta 39 (1992) 1449–1457, https://doi.org/10.1016/0039-9140(92)80125-W. [34] A.M. O’Mahony, J. Wang, Electrochemical detection of gunshot residue for forensic analysis: a review, Electroanalysis 25 (2013) 1341–1358, https://doi.org/10.1002/ elan.201300054. [35] D. Wu, D. Du, Y. Lin, Recent progress on nanomaterial-based biosensors for veterinary drug residues in animal-derived food, TrAC, Trends Anal. Chem. 83 (2016) 95–101, https://doi.org/10.1016/j.trac.2016.08.006. [36] J.R. Windmiller, J. Wang, Wearable electrochemical sensors and biosensors: a review, Electroanalysis 25 (2013) 29–46, https://doi.org/10.1002/elan.201200349. [37] B.B. Dzantiev, A.V. Zherdev, M.F. Yulaev, R.A. Sitdikov, N.M. Dmitrieva, I.Y. Moreva, Electrochemical immunosensors for determination of the pesticides 2,4-dichlorophe­ noxyacetic and 2,4,5-trichlorophenoxyacetic acids, Biosens. Bioelectron. 11 (1996) 179–185, https://doi.org/10.1016/0956-5663(96)83725-0. [38] W. Wojnowski, T. Majchrzak, T. Dymerski, J. Gębicki, J. Namieśnik, Portable electronic nose based on electrochemical sensors for food quality assessment, Sensors 17 (2017) 2715, https://doi.org/10.3390/s17122715. [39] M. Mir, A. Homs, J. Samitier, Integrated electrochemical DNA biosensors for labon-a-chip devices, Electrophoresis 30 (2009) 3386–3397, https://doi.org/10.1002/ elps.200900319. [40] S. Gupta, C.N. Murthy, C.R. Prabha, Recent advances in carbon nanotube based electrochemical biosensors, Int. J. Biol. Macromol. 108 (2018) 687–703, https://doi. org/10.1016/j.ijbiomac.2017.12.038. [41] D.W. Kimmel, G. Leblanc, M.E. Meschievitz, D.E. Cliffel, Electrochemical sensors and biosensors, Anal. Chem. 84 (2012) 685–707, https://doi.org/10.1021/ac202878q. [42] D.G. Rackus, M.H. Shamsi, A.R. Wheeler, Electrochemistry, biosensors and microfluidics: a convergence of fields, Chem. Soc. Rev. 44 (2015) 5320–5340, https://doi. org/10.1039/c4cs00369a. [43] N.P. Negi, T. Choephel, Biosensor: an approach towards a sustainable environment, in: M. Mohsin, R. Naz, A. Altaf (Eds.), Nanobiosensors for Agricultural, Medical and Environmental Application, Springer, Singpore, 2020, https://doi. org/10.1007/978-981-15-8346-9. [44] E.T. Power, F. Yalcinkaya, Intelligent biosensors, Sens. Rev. 17 (1997) 107–116, https:// doi.org/10.1108/02602289710170276. [45] S. Joseph, J.F. Rusling, Y.M. Lvov, T. Friedberg, U. Fuhr, An amperometric biosensor with human CYP3A4 as a novel drug screening tool, Biochem. Pharmacol. 65 (2003) 1817–1826, https://doi.org/10.1016/S0006-2952(03)00186-2.

108

Functionalized Nanomaterial-Based Electrochemical Sensors

[46] U. Yogeswaran, S.-M. Chen, A review on the electrochemical sensors and biosensors composed of nanowires as sensing material, Sensors 8 (2008) 290–313, https://doi. org/10.3390/s8010290. [47] Q. Liu, C. Wu, H. Cai, N. Hu, J. Zhou, P. Wang, Cell-based biosensors and their application in biomedicine, Chem. Rev. 114 (2014) 6423–6461, https://doi.org/10.1021/cr2003129. [48] J. Lao, P. Sun, F. Liu, X. Zhang, C. Zhao, W. Mai, T. Guo, G. Xiao, J. Albert, In situ plasmonic optical fiber detection of the state of charge of supercapacitors for renewable energy storage, Light Sci. Appl. 7 (2018) 2047–7538, https://doi.org/10.1038/ s41377-018-0040-y. [49] K. Habermüller, M. Mosbach, W. Schuhmann, Electron-transfer mechanisms in amperometric biosensors, Fresenius J. Anal. Chem. 366 (2000) 560–568, https://doi. org/10.1007/s002160051551. [50] S. Nabih, S.S. Hassn, Chitosan-capped Ag–Au/rGO nanohybrids as promising enzymatic amperometric glucose biosensor, J. Mater. Sci. Mater. Electron. 31 (2020) 13352– 13361, https://doi.org/10.1007/s10854-020-03889-4. [51] H.S. Yim, C.E. Kibbey, S.C. Ma, D.M. Kliza, D. Liu, S.B. Park, C.E. Torre, M.E. Meyerhoff, Polymer membrane-based ion-, gas- and bio-selective potentiometric sensors, Biosens. Bioelectron. 8 (1993) 1–38, https://doi.org/10.1016/0956-5663(93)80041-M. [52] F. Toldrá, L.M.L. Nollet, Advances in Food Diagnostics, vol. 2, Wiley Blackwell, 2017, pp. 1–528. ISBN: 978-1-119-10588-6 (Accessed 13 July 2020). [53] Y.V. Plekhanova, Y.E. Firsova, N.V. Doronina, Y.A. Trotsenko, A.N. Reshetilov, Aerobic methylobacteria as the basis for a biosensor for dichloromethane detection, Appl. Biochem. Microbiol. 49 (2013) 188–193, https://doi.org/10.1134/S0003683813020130. [54] A. Ma’mun, M.K. Abd El-Rahman, M. Abd El-Kawy, Real-time potentiometric sensor; an innovative tool for monitoring hydrolysis of chemo/bio-degradable drugs in pharmaceutical sciences, Sens. Actuators B 154 (2018) 166–173, https://doi.org/10.1016/j. jpba.2018.02.007. [55] G.S. Cha, M.E. Meyerhoff, Enzyme electrode-based differential potentiometric cell with enhanced substrate sensitivity, Electroanalysis 1 (1989) 205–211, https://doi. org/10.1002/elan.1140010304. [56] J.G. Schiller, A.K. Chen, C.C. Liu, Determination of phenol concentrations by an electrochemical system with immobilized tyrosinase, Anal. Biochem. 85 (1978) 25–33, https://doi.org/10.1016/0003-2697(78)90269-5. [57] G. Denuault, M.H.T. Frank, L.M. Peter, Scanning electrochemical microscopy: potentiometric probing of ion fluxes, Faraday Discuss. 94 (1992) 23–35, https://doi.org/10.1039/ FD9929400023. [58] R. Koncki, Recent developments in potentiometric biosensors for biomedical analysis, Anal. Chim. Acta 599 (2007) 7–15, https://doi.org/10.1016/j.aca.2007.08.003. [59] J. Ding, W. Qin, Recent advances in potentiometric biosensors, TrAC, Trends Anal. Chem. 124 (2020) 115803, https://doi.org/10.1016/j.trac.2019.115803. [60] R. Cánovas, P. Blondeau, F.J. Andrade, Modulating the mixed potential for developing biosensors: direct potentiometric determination of glucose in whole, undiluted blood, Biosens. Bioelectron. 163 (2020) 112302, https://doi.org/10.1016/j.bios.2020.112302. [61] C. Fernández-Sánchez, C.J. McNeil, K. Rawson, Electrochemical impedance spectroscopy studies of polymer degradation: application to biosensor development, TrAC, Trends Anal. Chem. 24 (2005) 37–48, https://doi.org/10.1016/j.trac.2004.08.010. [62] B. Lindholm-Sethson, J. Nyström, M. Malmsten, L. Ringstad, A. Nelson, P. Geladi, Electrochemical impedance spectroscopy in label-free biosensor applications: multivariate data analysis for an objective interpretation, Anal. Bioanal. Chem. 398 (2010) 2341–2349, https://doi.org/10.1007/s00216-010-4027-7.

Functionalized carbon material-based electrochemical sensors

109

[63] Y. Wang, Z. Ye, Y. Ying, New trends in Impedimetric biosensors for the detection of foodborne pathogenic bacteria, Sensors 12 (2012) 3449–3471, https://doi.org/10.3390/ s120303449. [64] F. Lisdat, D. Schäfer, The use of electrochemical impedance spectroscopy for biosensing, Anal. Bioanal. Chem. 391 (2008) 1555–1567, https://doi.org/10.1007/ s00216-008-1970-7. [65] N. Hareesha, J.G. Manjunatha, A simple and low-cost poly (DL-phenylalanine) modified carbon sensor for the improved electrochemical analysis of riboflavin, J. Sci. Adv. Mater. Devices 5 (2020) 502–511, https://doi.org/10.1016/j.jsamd.2020.08.005. [66] P.A. Pushpanjali, J.G. Manjunatha, Development of polymer modified electrochemical sensor for the determination of alizarin carmine in the presence of tartrazine, Electroanalysis 32 (2020) 2474–2480, https://doi.org/10.1002/elan.202060181. [67] N. Hareesha, J.G. Manjunatha, Fast and enhanced electrochemical sensing of dopamine at cost-effective poly(DL-phenylalanine) based graphite electrode, J. Electroanal. Chem. 878 (2020) 114533, https://doi.org/10.1016/j.jelechem.2020.114533. [68] N. Hareesha, J.G. Manjunatha, Elevated and rapid voltammetric sensing of riboflavin at poly(helianthin dye) blended carbon paste electrode with heterogeneous rate constant elucidation, J. Iran. Chem. Soc. (2020), https://doi.org/10.1007/s13738-020-01876-4. [69] G. Tigari, J.G. Manjunatha, C. Raril, N. Hareesha, Electrochemical determination of resorcinol with tartrazine at non-ionic surfactant modified graphite powder and carbon nanotube composite paste electrode, Nov. Appro. Drug Des. Dev. 4 (2019), https://doi. org/10.19080/NAPDD.2019.04.555647. [70] J.S. Daniels, N. Pourmand, Label-free impedance biosensors: opportunities and challenges, Electroanalysis 19 (2007) 1239–1257, https://doi.org/10.1002/elan.200603855. [71] X. Xu, S. Liu, B. Li, H. Ju, Disposable nitrite sensor based on hemoglobin-colloidal gold nanoparticle modified screen-printed electrode, Anal. Lett. (2003), https://doi. org/10.1081/AL-120024333. [72] S.A. Wring, J.P. Hart, Chemically modified, carbon-based electrodes and their application as electrochemical sensors for the analysis of biologically important compounds a review, Analyst (1992), https://doi.org/10.1039/AN9921701215. [73] E.R. Brown, T.G. McCord, D.E. Smith, D.D. DeFord, Some investigations on instrumental compensation of nonfaradaic effects in voltammetric techniques, Anal. Chem. 38 (1966) 1119–1129, https://doi.org/10.1021/ac60241a004. [74] N.S. Prinith, J.G. Manjunatha, Polymethionine modified carbon nanotube sensor for sensitive and selective determination of l-tryptophan, J. Electrochem. Sci. Eng. 10 (2020) 305–315, https://doi.org/10.5599/jese.774. [75] M. Zouari, S. Campuzano, J.M. Pingarrón, N. Raouafi, Determination of miRNAs in serum of cancer patients with a label- and enzyme-free voltammetric biosensor in a single 30-min step, Microchim. Acta 187 (2020) 1–11, https://doi.org/10.1007/ s00604-020-04400-w. [76] A. Herrera-Chacón, Ş. Dinç-Zor, M. del Valle, Integrating molecularly imprinted polymer beads in graphite-epoxy electrodes for the voltammetric biosensing of histamine in wines, Talanta 208 (2020) 120348, https://doi.org/10.1016/j.talanta.2019.120348. [77] C.M. Hussain, Handbook of Nanomaterials for Industrial Applications, 2018, https:// doi.org/10.1016/C2016-0-04427-3. [78] R. Chenthattil, J.G. Manjunatha, D.K. Ravishankar, S. Fattepur, G. Siddaraju, L. Nanjundaswamy, Validated electrochemical method for simultaneous resolution of tyrosine, uric acid, and ascorbic acid at polymer modified nano-composite paste electrode, Surf. Eng. Appl. Electrochem. 56 (2020) 415–426, https://doi.org/10.3103/ S1068375520040134.

110

Functionalized Nanomaterial-Based Electrochemical Sensors

[79] N. Hareesha, J.G. Manjunatha, Surfactant and polymer layered carbon composite electrochemical sensor for the analysis of estriol with ciprofloxacin, Mater. Res. Innov. 24 (2020) 349–362, https://doi.org/10.1080/14328917.2019.1684657. [80] N. Hareesha, J.G. Manjunatha, C. Raril, G. Tigari, Sensitive and selective electrochemical resolution of tyrosine with ascorbic acid through the development of electropolymerized alizarin sodium sulfonate modified carbon nanotube paste electrodes, ChemistrySelect 4 (2019) 4559–4567, https://doi.org/10.1002/slct.201900794. [81] N. Hareesha, J.G.G. Manjunatha, C. Raril, G. Tigari, Design of novel surfactant modified carbon nanotube paste electrochemical sensor for the sensitive investigation of tyrosine as a pharmaceutical drug, Adv. Pharm. Bull. 9 (2019) 132–137, https://doi. org/10.15171/apb.2019.016. [82] C. Raril, J.G. Manjunatha, A simple approach for the electrochemical determination of vanillin at ionic surfactant modified graphene paste electrode, Microchem. J. 154 (2020) 104575, https://doi.org/10.1016/j.microc.2019.104575. [83] S.R.C. Vivekchand, C. Sekhar, A. Govindaraj, R. Rao, Graphene-based electrochemical supercapacitors, J. Chem. Sci. 120 (2008) 9–13, https://doi.org/10.1007/ S12039-008-0002-7. [84] P. Simon, Y. Gogotsi, B. Dunn, Where do batteries end and supercapacitors begin? Science 343 (2014) 1210–1211, https://doi.org/10.1126/science.1249625. [85] J.J. Yoo, K. Balakrishnan, J. Huang, V. Meunier, B.G. Sumpter, A. Srivastava, M. Conway, A.L. Mohana Reddy, J. Yu, R. Vajtai, P.M. Ajayan, Ultrathin planar graphene supercapacitors, Nano Lett. 11 (2011) 1423–1427, https://doi.org/10.1021/nl200225j. [86] L. Wang, Y. Han, X. Feng, J. Zhou, P. Qi, B. Wang, Metal-organic frameworks for energy storage: batteries and supercapacitors, Coord. Chem. Rev. 307 (2016) 361–381, https://doi.org/10.1016/j.ccr.2015.09.002. [87] W. Zuo, R. Li, C. Zhou, Y. Li, J. Xia, J. Liu, Battery‐supercapacitor hybrid devices: recent progress and future prospects, Adv. Sci. 4 (2017), https://doi.org/10.1002/ [email protected]/(ISSN)2198-3844.EDITORS-CHOICE-REVIEWS. [88] V. Hoffmann, M.P. Olszewski, K.M. Swiatek, B. Musa, P.J.A. Gimeno, C.R. Correa, A. Kruse, Bio-based electric devices, in: Biobased Products and Industries, Elsevier, 2020, pp. 311–355, https://doi.org/10.1016/b978-0-12-818493-6.00009-9. [89] S. Palit, C.M. Hussain, Carbon‐based polymer nanocomposite and environmental perspective, in: Emerging Carbon-Based Nanocomposites for Environmental Applications, Wiley, 2020, pp. 121–145, https://doi.org/10.1002/9781119554882.ch5. [90] S. Korkmaz, A. Kariper, Graphene and graphene oxide based aerogels: synthesis, characteristics and supercapacitor applications, J. Energy Storage 27 (2020) 101038, https:// doi.org/10.1016/j.est.2019.101038. [91] N. Barsan, D. Koziej, U. Weimar, Metal oxide-based gas sensor research: how to? Sens. Actuators B 121 (2007) 18–35, https://doi.org/10.1016/j.snb.2006.09.047. [92] A. Modi, N. Koratkar, E. Lass, B. Wei, P.M. Ajayan, Miniaturized gas ionization sensors using carbon nanotubes, Nature 424 (2003) 171–174, https://doi.org/10.1038/ nature01777. [93] N. Yamazoe, Toward innovations of gas sensor technology, Sens. Actuators B Chem. (2005) 2–14, https://doi.org/10.1016/j.snb.2004.12.075. Elsevier. [94] N.M. Santhosh, A. Vasudevan, A. Jurov, A. Korent, P. Slobodian, J. Zavašnik, U. Cvelbar, Improving sensing properties of entangled carbon nanotube-based gas sensors by atmospheric plasma surface treatment, Microelectron. Eng. 232 (2020) 111403, https://doi. org/10.1016/j.mee.2020.111403.

Functionalized carbon material-based electrochemical sensors

111

[95] Y. Khan, A.E. Ostfeld, C.M. Lochner, A. Pierre, A.C. Arias, Monitoring of vital signs with flexible and wearable medical devices, Adv. Mater. 28 (2016) 4373–4395, https:// doi.org/10.1002/adma.201504366. [96] Y.L. Zheng, X.R. Ding, C.C.Y. Poon, B.P.L. Lo, H. Zhang, X.L. Zhou, G.Z. Yang, N. Zhao, Y.T. Zhang, Unobtrusive sensing and wearable devices for health informatics, IEEE Trans. Biomed. Eng. 61 (2014) 1538–1554, https://doi.org/10.1109/ TBME.2014.2309951. [97] G. Yang, L. Xie, M. Mäntysalo, X. Zhou, Z. Pang, L. Da Xu, S. Kao-Walter, Q. Chen, L.R. Zheng, A Health-IoT platform based on the integration of intelligent packaging, unobtrusive bio-sensor, and intelligent medicine box, IEEE Trans. Ind. Inform. 10 (2014) 2180–2191, https://doi.org/10.1109/TII.2014.2307795. [98] U. Kamran, Y.-J. Heo, J.W. Lee, S.-J. Park, Functionalized carbon materials for electronic devices: a review, Micromachines 10 (2019) 234, https://doi.org/10.3390/mi10040234. [99] T.Q. Trung, N.E. Lee, Flexible and stretchable physical sensor integrated platforms for wearable human-activity monitoring and personal healthcare, Adv. Mater. 28 (2016) 4338–4372, https://doi.org/10.1002/adma.201504244. [100] M. Amjadi, K.U. Kyung, I. Park, M. Sitti, Stretchable, skin-mountable, and wearable strain sensors and their potential applications: a review, Adv. Funct. Mater. 26 (2016) 1678–1698, https://doi.org/10.1002/adfm.201504755. [101] B. Wang, A. Facchetti, Mechanically flexible conductors for stretchable and wearable E-skin and E-textile devices, Adv. Mater. 31 (2019), https://doi.org/10.1002/ adma.201901408. [102] D.K. Subbiah, S. Balasubramanian, A.J. Kulandaisamy, K. Jayanth Babu, A. Das, J.B.B. Rayappan, Surface Modification of Textiles with Nanomaterials for Flexible Electronics Applications, Springer, Singapore, 2020, pp. 1–42, https://doi. org/10.1007/978-981-15-3669-4_1. [103] G. Mills, G. Fones, A review of in situ/IT methods and sensors for monitoring the marine environment, Sens. Rev. 32 (2012) 17–28, https://doi.org/10.1108/02602281211197116. [104] F. Scheller, F. Schubert, Biosensors, in: Techniques and Instrumentation in Analytical Chemistry, vol. 11, Elsevier, 1992, pp. 1–359. (Accessed 14 July 2020). [105] S. Li, X. Xiao, J. Hu, M. Dong, Y. Zhang, R. Xu, X. Wang, J. Islam, Recent advances of carbon-based flexible strain sensors in physiological signal monitoring, ACS Appl. Electron. Mater. 2 (2020) 2282–2300, https://doi.org/10.1021/acsaelm.0c00292. [106] K. Dong, X. Peng, Z.L. Wang, Fiber/fabric-based piezoelectric and triboelectric nanogenerators for flexible/stretchable and wearable electronics and artificial intelligence, Adv. Mater. 32 (2020), https://doi.org/10.1002/adma.201902549. [107] S. Sukumaran, S. Chatbouri, D. Rouxel, E. Tisserand, F. Thiebaud, T. Ben Zineb, Recent advances in flexible PVDF based piezoelectric polymer devices for energy harvesting applications, J. Intell. Mater. Syst. Struct. (2020), https://doi. org/10.1177/1045389X20966058, 1045389X2096605. [108] H. Montazerian, A. Rashidi, A.S. Milani, M. Hoorfar, Integrated sensors in advanced composites: a critical review, Crit. Rev. Solid State Mater. Sci. 45 (2020) 187–238, https://doi.org/10.1080/10408436.2019.1588705.

This page intentionally left blank

Section D Noble metals, non-noble metal oxides and non-carbon-based electrochemical sensors

This page intentionally left blank

Noble metals and nonnoble metal oxides based electrochemical sensors

7

Parisa Nasr-Esfahania and Ali A. Ensafia,b a Department of Chemistry, Isfahan University of Technology, Isfahan, Iran, bDepartment of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States

7.1 Introduction Today, sensors have attracted enormous attention due to their low cost and point-ofcare applications [1]. Recently, chemical sensors have become a significant part of modern society because of their widespread application in various environmental monitoring, pharmaceuticals, security, the food industry, and healthcare [2]. Among all chemical sensors, electrochemical sensors are widely used due to ease of use, simple instrumentation, minimal sample pretreatment, short analysis time, high sensitivity, and specificity. Also, they have already shown their advantages, and in terms of availability, they rank first. Furthermore, electrochemical measurement is preferable to other determination techniques because of its easy and quick characteristics [3]. Nanomaterials have attracted considerable interest in construction chemical sensors because of their excellent catalytic, electrical, optical, and thermal properties, which is due to their small size. Nanomaterials, especially nanoparticles, have become one of the most interesting fields in electrochemical sensors fabrication [4]. It is clear that the performance of the electrochemical sensors depends on the properties of electrode surface modifiers. Different nanoparticle types, such as noble metal nanoparticles, metal nanoparticles, metal oxide nanoparticles, quantum dots, etc., have been widely employed in the surface modification of electrodes (Fig. 7.1). These nanoparticles play different roles in electrochemical sensors, depending on their properties. For example, they can adsorb biomolecules because of their large specific surface area and high surface free energy and play a significant role in the immobilization of biomolecules. Also, some nanoparticles, especially metal nanoparticles, present excellent catalytic properties, and they can reduce the overpotentials of many electrochemical reactions. Moreover, metal nanoparticles’ conductivity properties increase the electron transfer between analytes and electrodes and act as electron transfer mediators. Nanoparticles can be used as labels for labeling biomolecules, such as antigen, antibody, and DNA, which is very useful in detecting a low concentration of analytes [5]. As well as, nanoparticles, due to their high surface energy, can act as a reactant. For example, bulk MnO2 can catalyze the decomposition of H2O2, while MnO2 nanoparticles can immediately react with H2O2 [6]. Moreover, they can facilitate analytical performance, including stability, detection limit, sensitivity, and multidetection ability [7]. Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00023-5 Copyright © 2022 Elsevier Ltd. All rights reserved.

116

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 7.1  Different types of nanoparticles for surface modification of electrode.

Nobel metal nanoparticles, as one of the important groups of nanomaterials, such as silver, platinum, palladium, and gold, have received a lot of attention in the fabrication of electrochemical sensors due to their unbeatable properties such as low cytotoxicity, biocompatibility, conductivity, and size-dependent chemical, electrical and magnetic properties [1,8]. Electrodeposition of noble metal nanoparticles, especially platinum and gold, is quickly done on the surface of any kind of working electrode [9]. In addition, ease of surface functionalization, dimension likeness with biomolecules, and large surface areas proper for immobilization of biomolecules make them an excellent choice as electrode surface modifiers for fabrication electrochemical biosensors [8].

Noble metals and nonnoble metal oxides based electrochemical sensors117

Also, extremely sensitive and cost-effective electrochemical sensors are fabricated on metal oxide nanoparticles with a wide range of applications for detecting various analytes. Nonnoble metal oxides nanoparticles such as Fe2O3, Fe3O4, MnO, TiO2, CuO, Cu2O, and ZnO, with various morphologies, are widely used both in their pristine form and in conjunction with other materials as electrode modifiers in electrochemical sensors fabrication. These nanoparticles possess interesting biocompatible, nontoxic, physicochemical, and helpful catalytic properties, making them appropriate options for detecting different analytes [10]. This chapter describes various properties of noble metal and nonnoble metal oxides nanoparticles. Different methods of modifying the electrode surface with these nanomaterials are reviewed. Furthermore, applications of noble metals and nonnoble metal oxides-based electrochemical sensors in various fields are presented.

7.2 Synthesis of noble metal and nonnoble metal nanoparticles At present, one of the main aspects of nanotechnology research is the development of new, efficient, promising, and rapid methods for the synthesis of nanoparticles due to their increased utilization in different applications. There are two general approaches for nanoparticle synthesis: top-down and bottom-up approaches (Fig. 7.2). In top-down

Fig. 7.2  Top-down and bottom-up approaches for the synthesis of nanoparticles.

118

Functionalized Nanomaterial-Based Electrochemical Sensors

methods, using a series of tools, the material is separated from the bulk, and the small object is reduced to nanometer size. In bottom-up methods, nanomaterials are produced by joining building blocks such as atoms and molecules and placing them next to each other or using self-assembly. The advantage of the top-down method is the mass production of nanomaterials in a short time. On the other hand, the advantage of the bottom-up method is that the nanostructures are homogeneous and are perfect in terms of crystallographic and surface structure [11].

7.2.1 Top-down methods As mentioned, the top-down methods rely on smaller units based on the breakdown of a larger unit. Micropatterning, pyrolysis, and attrition are the most used methods based on the top-down approach. In the micropatterning technique, nanostructures are removed from a precursor material using a focused beam of light (UV or X-ray), electrons, or ions [12]. This method is extensively used for the synthesis of nanoparticles in electronics. The most popular method of micropatterning is photolithography. Many other methods have been extended in recent years, including colloidal lithography, E-beam lithography, nanocontact printing, nano-imprint lithography, nanosphere lithography, and scanning lithography, scanning probe lithography, and soft lithography [13]. The most widely used technique for the production of noble metal nanoparticles is pyrolysis. In this technique, a pure and inert carrier gas enters the chamber containing the liquid precursor for nanoparticle production. The precursor in this chamber is decomposed by a burner and sent to the refrigerator by the carrier gas. The steams are cooled and form into grains or clusters. However, this technique’s main limitation is the high amount of energy required to perform the decomposition process [14]. In the attrition process, macro and micro-scale materials are ground in a ball mill to produce nano-size materials. Different parameters, including milling temperature, milling time, the ball to powder weight ratio, milling atmosphere, milling intensity, and type of mill, affect the physical properties, shape, and size of nanoparticles. Various milling devices such as attrition mills, planetary mills, shaker mills, tumbler mills, and vibratory mills have been developed for various purposes and nanoparticles with various properties. The attrition process is a double-edged sword technique and has pros and cons. This method is beneficial for the mass production of nanoparticles. This approach is also beneficial for the production of nanocomposites and alloys that cannot be synthesized by conventional methods. The disadvantages of this technique include imperfect surface structure, contamination, and internal stress. The imperfect surface structure alters the surface chemistry and physicochemical properties of synthesized nanoparticles [11].

7.2.2 Bottom-up methods These methods are based on molecular recognition and molecular self-assembly. As mentioned, bottom-up methods utilize chemical or physical forces to assemble basic units into larger structures. Different types of bottom-up methods, including

Noble metals and nonnoble metal oxides based electrochemical sensors119

chemical reduction, microemulsion, electrochemical method, laser ablation, and microwave method, have been devoted to synthesizing nanoparticles that are briefly debated below [11]. The chemical reduction technique is one of the most widely used techniques for preparing a noble metal nanoparticle. This method is used for metal nanoparticle synthesis in solutions [15]. Chemical reduction of the salt solution of the corresponding metal is carried out in the presence of a stabilizing agent and different reducing agents such as alcohols, carbon monoxide, hydrazine, hydrogen, NaBH4, and LiAlH4 [16]. So far, the synthesis of gold [17], silver [18], and platinum [19] nanoparticles has been reported using this method. However, chemical reduction is a simple, convenient, and common method for synthesizing noble metal nanoparticles, and it has some drawbacks. It is challenging to create the right conditions, such as high temperature and pressure, to perform these reactions. Moreover, the required time to complete this reaction is long. Also, most of the used reactants in this method are toxic, dangerous for the environment, and health. Furthermore, the use of synthesized nanoparticles by this method for biological applications is limited due to stabilizing molecules on their surface [20]. Microemulsion method was first used in the early 1980s to prepare palladium, platinum, and rhodium nanoparticles. In this method, at first, salts and reducing agents are dispersed in water-in-oil or water-in-water emulsions, and then these two separate emulsions are mixed in the presence of surfactants. Intermicellar collisions caused by the Brownian motion of the formed micelles contribute to nucleation and nanoparticles’ production. The synthesized nanoparticles by this method are monodispersed and thermodynamically stable [21]. Among the various methods for nanoparticle synthesis, electrochemical methods have attracted considerable attention. Because electrochemical deposition is easy, it requires simple equipment, and accumulation control is possible with voltage, current, and solution concentration control. Electrochemical techniques are very attractive because they do not require high temperatures, are compatible with a wide range of substrate materials, lead to high effective surface area production, and are environmentally friendly. Electrochemical methods also make it possible to produce nanoparticles with high purity and desired morphology. So far, various electrochemical methods have been developed to synthesize noble metal nanoparticles [22–24]. The electrochemical process for producing noble metal nanoparticles is performed using a two-or three-electrode system, and the electrolyte solution acts as the source of noble metal [25]. By controlling the potential or current, the nanoparticles precipitate on the surface. In other words, the oxidized form in the solution becomes the metal form on the surface. There are different electrochemical methods for the fabrication of nanoparticles, such as pulsed electrodeposition [26], cyclic voltammetry [27], squarewave voltammetry [28], chronoamperometry [29], chronopotentiometry [30], and chronocoulometry [31]. In the laser ablation method, the materials are removed from a solid surface by laser radiation. Actually, the laser beam is focused on the surface of the sample immersed in the liquid. By applying a few pulses, the particles are separated from the surface of the sample. If the laser energy is low, the material will evaporate or sublimate, but

120

Functionalized Nanomaterial-Based Electrochemical Sensors

the material will turn into plasma if the laser energy is high. The amount of removed material in this method depends on the optical properties of the material and the laser’s wavelength. This method makes it possible to synthesize nanoparticles in aqueous or organic solvents. For this reason, in recent years, the laser ablation method has been used as an alternative for the chemical reduction method to synthesize noble metal nanoparticles in the solution phase. The most important advantages of this method are the production of homogeneous and uniform nanoparticles, control size and composition and morphology, repeatability, high performance, efficient cost, and time [32]. The basis of the microwave method for the production of nanoparticles is the irradiation of solutions containing salts and polymer surfactants with microwaves. Due to microwaves’ unique properties, these waves have been widely used in the synthesis of various nanomaterials, especially noble metal nanoparticles [11]. The microwave heating process is selective because all materials are not able to absorb microwaves. Therefore, the selectivity of heat production with microwaves is one of its most prominent features. When nanomaterials are synthesized using traditional and conventional heating systems, the reaction vessel acts as an intermediate in the transfer of energy from the source to solvent and reactive molecules, creating an intense thermal gradient in the solution as well as nonuniformity and reaction efficiency will significantly reduce. Due to the fact that the final properties and quality of nanomaterials depend on the speed of germination and growth, this nonuniformity has caused problems in the synthesis of nanoparticles with traditional and conventional heating systems. In contrast, microwave heating can significantly reduce the problems caused by nonuniform heating. The initial heating rate (reaching the desired temperature to start the reaction) is increased using a microwave, and the synthesis process is accelerated. Therefore, as the chemical reaction time decreases from a few hours to a few minutes, the energy efficiency will also increase. The morphology, shape, and size of the nanoparticles produced can be adjusted by optimizing the reaction’s parameters. This method has so far been used for the successful synthesis of gold, silver, and platinum nanoparticles [13].

7.3 Noble metal-based electrochemical sensors Remarkable research has been performed on developing noble metal nanomaterials-­ based electrochemical sensors due to their unique electrochemical properties. Actually, noble metal nanoparticles play an essential role in the fabrication of electrochemical sensors due to their facile synthesis, ease of functionalization, catalysis of electrochemical reactions, and increment of the electron transfer [10]. For these reasons, in this section, the properties of noble metal nanoparticles are described. Also, applications of noble metal-based electrochemical sensors in diverse fields are reviewed.

7.3.1 Gold nanoparticles Gold nanoparticles can be coated with different materials such as small molecules, biomolecules, and polymers because of these nanoparticles’ versatile surface chemistry.

Noble metals and nonnoble metal oxides based electrochemical sensors121

Therefore, they have a wide range of applications in different fields, such as catalysis, sensory probes, drug delivery, and therapeutic agents. Recently, gold nanoparticles are known as an ideal modifier for electrode surface in electrochemical sensors fabrication. Wide applications of gold nanoparticles for the fabrication of electrochemical sensors are due to their excellent properties such as tunable physiochemical properties, outstanding electrical conductivity, oxidation resistance, high stability, simple preparation, narrow size distribution, excellent biocompatibility, capacity for surface modification, large surface area, and excellent catalytic activities [33,34]. Furthermore, the deposition of gold nanoparticles on the surface of various electrodes is quickly done. They play a critical role in decreasing the overpotentials of electrochemical reactions, which has made them very attractive surface modifiers [33]. Also, an essential factor that makes the use of gold nanoparticles efficient in electrochemical sensor fabrication is their morphology. The gold nanoparticles have spherical morphology, and they appear as a brown powder [8]. Unfortunately, despite all these advantages, the high price of gold nanoparticle-based materials has limited their widespread use for electrode surface modification [33]. Gold nanoparticles provide a unique perspective for sensors by making it possible to miniaturize electrochemical sensors to the nanometer scale. Miniaturized electrochemical sensors based on gold nanoparticles made using micro and nanofabrication technologies present an interesting method for developing electrochemical sensor array platforms. On the other hand, combining the electrochemical sensor with microfluidic devices makes the possibility for the simultaneous detection of analytes in a selective and sensitive technique [35]. High selectivity, desirable diffusion of electroactive species, great signal-to-noise ratio, and improved catalytic activity are advantages of using gold nanoparticles-based modified electrodes.

7.3.2 Silver nanoparticles Silver is an ideal metal for surface electrode modification and has the highest conductivity and stability among metals. Silver nanoparticles have absorbed a lot of attention for a wide range of applications. It has been proven that silver nanoparticles are one of the distinguished groups of nanomaterials for biological and therapeutic applications. Due to the excellent conductivity, amplified electrochemical signal, and good biocompatibility, these nanoparticles have had a significant effect on the world of electrochemical sensors and biosensors. However, they are not as widely studied as gold nanoparticles. Silver nanoparticles, like gold nanoparticles, have high electrical conductivity and can improve electron transfer between analytes and electrodes. Silver nanoparticles have catalytic redox properties for some biological and chemical agents. Electrochemical sensors based on silver nanoparticles make it possible to create early diagnostic tools for pathogens, infectious, and biological agents. These nanoparticles, because of their antimicrobial and catalytic properties, have been used in the manufacture of cosmetics, water purification, and environmental remediation. Using a combination of silver nanoparticles in matrices such as polymers, metal oxides, graphene, silicate, dendrimers, and fibers makes it possible to fabricate high-stability electrochemical sensors. The dispersion and prevention of silver nanoparticles’ agglomeration

122

Functionalized Nanomaterial-Based Electrochemical Sensors

in these matrices have created high sensitivity and stability for electrochemical sensors. The reason for the stability of silver nanoparticles in these matrices is that these nanoparticles are stable in these matrices due to the electrostatic repulsion with the matrices [34].

7.3.3 Platinum nanoparticles Another main group of noble metal nanoparticles is platinum nanoparticles. In nanotechnology, progression has caused the utilization of platinum nanoparticles for different fields such as cosmetics, pharmaceutical, catalysis, and biomedical applications. The catalytic performance of platinum nanoparticles depends on their composition, size, and morphology. Many efforts have been made to increase the efficiency of platinum catalysts to reduce the use of platinum because platinum is a rare and precious metal [36]. Chemical reactivity, interatomic bond distances, and electronic features can easily affect the platinum nanoparticles’ properties. On the other hand, crystal structure, surface condition, and chemical composition can dramatically change these nanoparticles’ electron transfer process. Platinum nanoparticles have attracted enormous attention for electrochemical sensor fabrication due to their interesting electronic and electrocatalytic properties, including excellent sensing and catalytic performance, low background current, good stability, and chemical inertness. An efficient manner toward developing the electrochemical properties of these nanoparticles is to make platinum nanocomposites-based electrodes [37,38].

7.3.4 Palladium nanoparticles Palladium, which is known as a member of the platinum group metals, has been extensively used in various fields such as catalysts and sensors to detect biomolecules, gases, and toxic molecules. Like other noble metals, palladium nanoparticles are used to make a variety of electrochemical sensors. Palladium nanoparticles-based electrodes have a high electrocatalytic activity toward diverse analytes. Palladium nanoparticles compared to gold and platinum nanoparticles have attracted enormous attention as catalysts because of their abundance, lower cost, and higher resistance to CO. Palladium-based electrocatalysts improve the electron transfer between the analyte and the electrode by improving the mass emission of the analytes, which creates electronic tunnels [39].

7.3.5 Application of noble metal-based electrochemical sensors Improving the sensitivity and detection strength of electrochemical sensors depends on the electrode materials used to manufacture the electrochemical sensors. Noble metal nanoparticles are suitable and widely used to manufacture electrochemical sensing platforms to detect various molecules with high sensitivity and selectivity. Noble metals nanoparticles by increasing the electrode’s active surface area to absorb target molecules and accelerate the transfer of electrons between the electrode and the molecules cause a rapid and sensitive response [36]. This section will examine the application of electrochemical sensors based on noble metals in various fields.

Noble metals and nonnoble metal oxides based electrochemical sensors123

7.3.5.1 Glucose detection The development of electrochemical sensors for glucose determination as one of the most critical small biomolecules has attracted much attention. This is because glucose level sensing is essential in blood for the treatment of diabetes. However, enzymatic electrochemical sensors based on glucose oxidase that catalyzes glucose oxidation to gluconolactone for glucose determination present high sensitivity and selectivity. But they have disadvantages such as the high price of enzymes and insufficient longterm stability. Therefore, the design of nonenzymatic electrochemical sensors for glucose measurement has attracted considerable attention [40]. Fortunately, noble metals nanoparticles exhibit a catalytic effect in the oxidation process of glucose, and noble metal-based electrochemical sensors are widely used for glucose determination. Shamsabadi et  al. demonstrated that gold nanoparticles incorporated graphene nanofibers had a remarkable enhancement of electrocatalytic activity for glucose oxidation. They prepared a nonenzymatic glucose electrochemical sensor based on a glassy carbon electrode decorated with gold nanoparticles incorporated graphene nanofibers. This electrochemical sensor showed a linear sensing response to glucose in the concentration range of 0.5–9.0 mM and a detection limit of 55 μM [41]. Xu et al. successfully fabricated a novel nonenzymatic electrochemical sensor based on gold nanoparticles/nickel hydroxide nanosheet nanocomposite for glucose detection in food samples. The presented sensor exhibited a wide linear range from 0.002 to 6.0 mM, a low detection limit of 0.66 μM, and good reproducibility and stability. These excellent analytical features are first attributed to the small size of gold nanoparticles, which increase the surface area of Ni(OH)2 sheets and the excellent conductivity of gold nanoparticles, thereby increasing electron transfer [42]. Mishra et al. developed a nonenzymatic and easily constructed glucose sensor based on gold nanoparticles modified copper oxide nanowires electrode on copper foil. Gold nanoparticles were synthesized using in situ chemical reactions on CuO nanowires electrode. The presence of gold nanoparticles on the CuO nanowires surface increased the surface-to-volume ratio, which increased the catalytic capability of gold nanoparticles modified CuO nanowires compared to the bare CuO nanowires. This nonenzymatic glucose sensor showed a linearity range from 0.5 to 5.9 mM and a detection limit of 0.5 mM [43]. Deshmukh et al. demonstrated silver nanoparticles decorated polyaniline and reduced graphene oxide had excellent electrochemical properties for glucose detection compared to polyaniline and polyaniline/reduced graphene oxide. This is due to the electronic interaction of silver nanoparticles with N atoms of polyaniline backbone in reduced graphene oxide for enhanced electronic transfer and the large surface area of silver nanoparticle/polyaniline/reduced graphene oxide. This nanocomposite was synthesized by a simple electrochemical method at room temperature. The proposed sensor exhibited a linear range from 50 to 0.1 μM and a detection limit of 0.79 μM [44]. Usman et al. developed a novel three-dimensional electrode based on silver nanoparticles for nonenzymatic glucose detection. Carbon nonocoils were grown on nickel foam surfaces by chemical vapors deposition to form a carbon nonocoils/nickel foam substrate. Subsequently, the 3D substrate was coated with silver nanoparticles/sheets through electrodeposition to form a carbon silver nanoparticles/nonocoils/nickel foam electrode. The presented sensor showed a wide linear range from 0.5 to 7.0 mM

124

Functionalized Nanomaterial-Based Electrochemical Sensors

and a low detection limit of 0.6 nM [45]. Khalaf et al. fabricated N/S-doped carbon-­ supported silver nanoparticles using a silver complex of chitosan polymer that exhibited excellent electrocatalytic activity toward glucose oxidation because of catalytic nature, good conductivity, and larger surface area (Fig. 7.3). Also, the presence of the heteroatom and silver nanoparticles into the carbon matrix increased the selectivity for glucose in an aqueous solution with interfering agents. The fabricated glucose sensor exhibited a low detection limit (0.046 mM), and a wide linear response was obtained from 5 μM to 3 mM [46]. Ensafi et al. prepared an efficient, fast, and stable nonenzymatic glucose sensor by decorating silver nanoparticles on organic functionalized multiwall carbon nanotubes. Electrochemical data showed that combining the unique properties of multiwall carbon nanotubes with the electrocatalytic effects of silver nanoparticles led to an increase in the sensor’s response to glucose. The sensor exhibited a detection limit of 0.03 mM, as well as a linear dynamic range of 1.3–1000 mM [47]. Zhu et al. synthesized platinum nanoparticles on the surface of 3D graphene and used it for modification of a glassy carbon electrode as a nonenzymatic sensor for glucose determination. This sensor showed two linear dynamic ranges from 0.1 μM to 0.01 mM and 0.01 to 20 mM, with a low detection limit of 30 nM [48]. Hoa et al. constructed a nonenzymatic glucose sensor composed of platinum nanoparticles and 3D graphene hydrogel by hydrothermal method. The proposed sensor showed excellent sensitivity and selectivity good selectivity and a wide linear range (5–20 mM)

Fig. 7.3  The synthesis routes for N/S-doped carbon-supported silver nanoparticles for glucose determination [46]. From N. Khalaf, T. Ahamad, M. Naushad, N. Al-hokbany, S.I. Al-Saeedi, S. Mutehri, S.M. Alshehri, Chitosan polymer complex derived nanocomposite (AgNPs/NSC), Int. J. Biol. Macromol. 146 (2020) 763–772.

Noble metals and nonnoble metal oxides based electrochemical sensors125

owing to the large surface area, high electrical conductivity, and electrocatalytic effects of platinum nanoparticles. These nanoparticles also prevent the agglomeration of graphene sheets [49]. Su et al. reported an electrochemical sensor based on platinum nanoparticles supported onto mesoporous carbons to detect glucose. Platinum nanoparticles-mesoporous carbons composite showed good electrocatalytic activity toward the oxidation of glucose with a linear range from 5 μM to 7.5 mM and a detection limit of 3 μM [50]. Shishegari et  al. developed a novel highly sensitive and selective nonenzymatic sensor for glucose detection based on palladium nanoparticles/NiAl layered double hydroxide, which modified the graphite sheet electrode covered by nitrogen-doped functionalized graphene. The sensor displayed great catalytic performance for glucose oxidation with a wide linear range of 500 nM to 10 mM, and a low detection limit of 234 nM, which could be attributed to the Ni and palladium active centers accelerates the transfer of electrons [51]. Wang et al. synthesized palladium nanoparticles/ nickel‑phosphorus nanosheets, which presented a large electrochemical active surface toward glucose oxidation reaction with a wide linear range (2 μM–4.65 mM) and a detection limit of 0.91 μM as a nonenzymatic glucose sensor. Actually, the synergistic combination of palladium nanoparticles and nickel phosphide nanostructure brings about excellent merit in the aspects of glucose oxidation [52]. Zhang et al. synthesized palladium nanoparticles on a porous gallium nitride electrode via in situ photodeposition to construct a nonenzymatic electrochemical sensor to detect glucose. Compared to other palladium-based electrochemical sensors for glucose detection, this electrode exhibited high sensitivity due to the uniform distribution and increased dispersity of high-density palladium nanoparticles. Its detection limit was 1 μM and presented two well linear relationships between the current and glucose concentration in the range of 1 μM–1 mM and 1–10 mM [53].

7.3.5.2 Hydrogen peroxide sensors Hydrogen peroxide (H2O2) is widely used in many fields, including the environment, food, industry, and medicine, due to its unique oxidizing and reducing properties. Also, H2O2 acts as a regulator of biological processes in the body of living organisms. Its abnormal concentration can still harm lysosomal membranes, cause severe injury to cells, and many diseases such as Alzheimer’s, Parkinson’s, diabetes, and cancer. Therefore, the development of sensitive, simple, fast, and stable methods for H2O2 detection has attracted the attention of many electrochemists. Unfortunately, electrochemical sensors based on enzymes are expensive and sensitive to temperature and pH. Also, enzyme stabilization methods on the electrode surface are time-consuming and complicated, and toxic chemicals affect enzyme activity [54]. For this reason, extensive studies have been conducted on the development of nonenzymatic electrochemical sensors for H2O2 detection. Jia et al. fabricated nonenzymatic electrochemical sensors based on gold nanoparticles/graphene/chitosan nanocomposite for H2O2 detection. Gold nanoparticles were electrochemically deposited on the graphene and chitosan-modified glassy carbon electrode. Compared with the bare glassy carbon electrode, the high specific area and good conductivity of graphene/chitosan increased the amount of electrodeposited gold

126

Functionalized Nanomaterial-Based Electrochemical Sensors

nanoparticles, which exerted high catalytic activity and facilitated the electrochemical reduction of H2O2. The fabricated sensor showed a linear range from 5.0 μM to 35 mM, with a detection limit of 1.6 μM [55]. Yang’s group developed a selective and sensitive nonenzymatic H2O2 electrochemical sensor based on loading gold nanoparticles on graphene sheets/cerium oxide nanocomposites modified gold electrode. The presented sensor exhibited high response currents and premiered electrochemical activity for H2O2 detection because of a good synergistic effect. Also, a broad linear detection ranges from 1.0 × 10− 3 mM to 10.0 mM, and a low limit of detection of 2.6 × 10− 4 mM was obtained [56]. Narang et al. constructed an electrochemical sensor based on polyaniline, multiwalled carbon nanotubes, and gold nanoparticles modified gold electrodes. The gold electrode was modified electrochemically with polyaniline and then immersed into the multiwalled carbon nanotubes solution and gold nanoparticles colloids, respectively. Enhanced electrochemical oxidation toward H2O2 was attributed to the enhanced direct electrochemistry of gold nanoparticles and the large surface of the multiwalled carbon nanotubes. The amperometric response to H2O2 showed a linear relationship in the range from 3.0 to 600 mM with a detection limit of 0.3 mM [57]. Ma et  al. prepared a nonenzymatic H2O2 electrochemical sensor using silver nanoparticles and a 2D copper-porphyrin framework (MOF). A practical method to improve MOF nanosheets’ performance is the combination of them with other nanomaterials and using synergies between them. The sensor exhibited a linear range from 3.7 μM to 5.8 mM and a low detection limit of 1.2 μM [58]. Aparicio-Martinez’s group displayed the detection of H2O2 with a nonenzymatic electrochemical sensor based on a laser scribed graphene electrode decorated with silver nanoparticles. In this sensor, combining the excellent properties of laser scribed graphene, including three-dimen­ sional architecture, exfoliation, oxygen removal, and edge plane exposure with silver nanoparticles’ electrocatalytic activity, increased the sensor’s response to the detection of H2O2. The sensor showed a linear range from 0.1 to 10 mM, a low LOD of 7.9 μM [59]. Gholami and Koivisto proposed a simple and selective nonenzymatic electrochemical sensor for H2O2 detection based on Nafion and silver nanoparticles composite coated carbon microfibers. Silver nanoparticles were electrodeposited on the carbon microfibers, which were imbued with Nafion as an ionic conductive substrate. The Nafion and silver nanoparticles composite-based sensor presented a linear range for H2O2 from 2.0 to 10 mM and a detection limit of 0.48 μM [60]. Zalneravicius et  al. designed an electrochemical detection platform for H2O2 based on molybdenum disulfide nanocomposites decorated with platinum nanoparticles (Fig.  7.4). Platinum nanoparticles were electrochemically deposited on molybdenum disulfide. Platinum nanoparticles improved the catalytic performance, and molybdenum disulfide enhanced the electrode surface and acted as a supporting material for platinum nanoparticles. This sensor displayed a detection limit of 42 nM [61]. Jimenez-Perez’s group constructed a novel nonenzymatic H2O2 sensor based on platinum nanoparticles electrochemically deposited on screen-printed carbon electrodes that were modified with poly(azure A). The simultaneous presence of platinum nanoparticles and poly(azure A) on a screen-printed carbon electrode surface prevented nanoparticles’ accumulation and increased their electrocatalytic activity for H2O2 oxidation. This sensor showed an excellent linear response from 0 to 300 μM and

Noble metals and nonnoble metal oxides based electrochemical sensors127

Fig. 7.4  Synthesis of nanoplatelet molybdenum disulfide arrays decorated with platinum nanoparticles to detect hydrogen peroxide [61]. From R. Zalnėravicius, A. Gedminas, T. Ruzgas, A. Jagminas, Nanoplatelet MoS2 arrays decorated with Pt nanoparticles for non-enzymatic detection of hydrogen peroxide, J. Electroanal. Chem. 839 (2019) 274–282.

a limit of detection of 51.6 nM [62]. Thirumalraj et al. developed a sensitive amperometric sensor to detect H2O2 using platinum nanoparticles decorated graphite/gelatin hydrogel. Gelatin hydrogel was considered for its advantages, such as dispersing medium and supporting agents for H2O2 molecule on the electrode surface. This sensor presented the higher electrocatalytic activity and superior conductivity of platinum nanoparticles on a graphite/gelatin hydrogel composite surface. The developed sensor displayed a wide linear response range of H2O2 concentrations from 0.05 to 870.6 μM with a detection limit of 37 nM [63]. Baghayeri’s group fabricated a nonenzymatic electrochemical sensor for the determination of H2O2. For this purpose, magnetic graphene oxide is decorated with palladium nanoparticles functionalized with amine-terminated poly(amidoamine) dendrimer. The presence of amine-terminated poly(amidoamine) dendrimer on the magnetic graphene oxide nanosheets provided numerous binding sites for palladium nanoparticles. Moreover, this polymer’s hyperbranched structure is very conducive to capturing nanosized palladium in a good dispersion form. These dramatically increased the electrocatalytic efficiency of the developed sensor to measure H2O2. The offered H2O2 sensor showed a linear range from 0.05 to 160 μM and a detection limit of 0.01 μM [64]. Guler and Dilmac fabricated a nonenzymatic H2O2 sensor based on palladium nanoparticles loaded (3-aminopropyl) triethoxysilane functionalized reduced graphene oxide modified glassy carbon electrode. Reduced graphene oxide/(3-­aminopropyl) ­triethoxysilane/ palladium nanoparticles composite improved the sensor’s electrocatalytic activity effectively. The linear range of the sensor for the H2O2 concentration detection was from 0.7 μM to 13.5 mM with a detection limit of 0.21 μM [65].

7.3.5.3 Environmental applications Increasing population growth, increasing demand for food and other human needs, developing the tourism industry, the spread of urbanization, and the intensification of environmental pollution (water, soil, and air) have seriously endangered the health

128

Functionalized Nanomaterial-Based Electrochemical Sensors

and lives of living organisms, especially humans. Heavy metals, inorganic anions, pesticides, and phenolic compounds are among the substances that cause irreparable damage to the environment and human health and lead to dangerous diseases such as cancer [34]. Therefore, the development of rapid, sensitive, and cost-effective methods is significant for detecting environmental pollution. Recently, electrochemical sensor based on noble metal nanoparticles has attracted a lot of attention for environmental applications. Arsenic is a heavy metal that poses a serious threat to humans and the environment. A sensitive electrochemical sensor for detecting As(III) in tap water and spring water samples was designed based on gold nanoparticles by Bu co-workers. For this purpose, three-dimensional porous graphitic carbon nitride was decorated by gold nanoparticles and cast on the glassy carbon electrode. The synergistic effect of the simultaneous presence of graphitic carbon nitride due to its porous structure and gold nanoparticles due to high electrocatalytic activity led to the ultrasensitive detection of As(III). Under an optimum condition, for the As(0)-As(III) oxidation linear range was obtained from 0.005 to 1.00 mM with a sorely low limit of detection of 2.9 nM. Meanwhile, the peak current for the As(III)-As(V) oxidation was also linear with As(III) concentration from 0.05 to 1.0 μM and a detection limit of 16 nM. The prepared sensor was successfully applied for As(III) in real water samples [66]. Cd2 + and Pb2 + are heavy metal ions that are not biodegradable and can accumulate in the human body and cause damage to the central nervous, immune, and reproductive systems. Qin et al. reported a simple and sensitive electrochemical sensor for the simultaneous detection of Cd2 + and Pb2 + in river water samples using gold nanoparticles functionalized β-cyclodextrin -graphene hybrids. β-cyclodextrin has multiple hydroxyl groups that can form complex with Cd2 + and Pb2 + and enrich the electrode’s surface, but it has poor conductivity. In contrast, gold nanoparticles can effectively enhance the conductivity of the modified electrode. Therefore, gold nanoparticles/β-cyclodextrin/ graphene-modified electrode showed good ability toward Cd2 + and Pb2 + detection. The linear range for the Cd2 + and Pb2 + concentration was 40–1200 μg L− 1and the detection limit was 24.8 μg L− 1 and 15.8 μg L− 1, respectively [67]. Cyanide (CN−) is one of the most hazardous environmental pollutants due to its low toxicity concentration. Shamsipur et al. developed a modified carbon ceramic electrode with gold nanoparticles for the detection of cyanide CN−. Gold nanoparticles were electrochemically deposited on a carbon-ceramic electrode. The proposed sensor showed a good linear range (0.5–14.0 μM) and a low detection limit (0.09 μM). It was also used for CN− determination in groundwater, tap water, and boiled water samples [68]. Phenolic compounds are environmental pollutants that remain in the environment for a long time and have toxic effects on humans and animals. Bo and Zhibo used gold nanoparticles decorated carbon nanotubes electrode to measure phenol in petrochemical wastewater. Carbon nanotubes were prepared via the chemical vapor deposition method, and gold nanoparticles were decorated on them by electrochemical deposition. This sensor has a lower detection limit than reported other sensors for phenol measurement, which is due to the high porosity of good stability gold nanoparticles on the carbon nanotubes surface. The linear range and detection limit were evaluated 1–200 μM, and 6 nM, respectively [69].

Noble metals and nonnoble metal oxides based electrochemical sensors129

Eksin co-workers developed an eco-friendly and disposable electrochemical sensor based on herbal silver nanoparticles for Hg2 + detection in tap water samples. They modified the surface of a pencil graphite electrode with silver nanoparticles and folic acid, respectively. Folic acid prevents the aggregation of silver nanoparticles by binding its amine groups to silver nanoparticles, and acid groups stabilize the silver nanoparticles by electrostatic repulsion; thereby, the silver nanoparticles’ electrocatalytic activity increases. The sensor response was proportional to the amount of Hg2 + in the range of 10 μM–25 mM, and the limit of detection was 8.43 μM [70]. Nitrite (NO2−) lowers the blood’s ability to transport oxygen through an irreversible reaction to hemoglobin. High levels of NO2− in the environment and nutrients have detrimental effects on human health. Ning’s group reported the fabrication of a NO2− electrochemical sensor based on PAMAM dendrimer stabilized silver nanoparticles. The silver nanoparticles-PAMAM modified glassy carbon electrode showed great electrocatalytic performance for the oxidation of nitrite. The improved electrochemical response of the proposed sensor to NO2 could be attributed to the increased surface area and silver nanoparticles’ excellent conductivity. This sensor exhibited a linear range from 4.0 μM to 1.44 mM with a detection limit of 0.4 μM. The proposed sensor was utilized to determine NO2− in tap water and milk samples [71]. Imidacloprid is one of the pesticides used to kill insects. Residual toxins in the environment and agricultural products affect human health. Pan et  al. proposed a simple electrochemical sensor based on silver nanoparticle detection of imidacloprid in the soil sample. Silver nanoparticles were synthesized by a biosynthesis method using Hypnea musciformis extract and dropped on a glassy carbon electrode surface. The presence of biomolecules on the surface of the silver nanoparticles prevents their aggregation. A linear detection range was obtained at 0.05–80 μM, and the detection limit was estimated as 0.02 μM [72]. Phenol-based aromatic nitro compounds are widely used in the chemical and pharmaceutical industries, known as a dangerous pollutant in the food chain and water. Laghrib’s group reported an electrochemical sensor for detecting p-nitrophenol using silver nanoparticles stabilized in β1,4-poly(d-glucosamine) modified graphite carbon electrode. The results showed that sensor response was linear to p-nitrophenol concentration in a range from 1.0 × 10− 6 to 1.0 × 10− 4 M with a detection limit of 6.0 × 10− 7 M. The proposed sensor was successfully used for p-nitrophenol detection in wastewater and river water samples [73]. Sheng et  al. fabricated a novel nitrite electrochemical sensor based on platinum nanoparticles loaded Ni(OH)2/multiwalled carbon nanotubes nanocomposites. Here, the deposition of Ni(OH)2 and multiwalled carbon nanotubes on the surface of a glassy carbon electrode increased the surface area. Therefore, the available surface for loading the platinum nanoparticles increased, which improved the electrical conductivity and electrocatalytic activity of the platinum nanoparticles. The proposed sensor exhibited a detection limit of 0.13 μM with a wide range between 0.4 μM and 5.67 mM based on the amperometric results [74]. Song’s group prepared a low-cost and straightforward electrochemical platform for phenol sensing based on a carbon paper electrode modified with graphite-like carbon nitride and platinum nanoparticles. Platinum nanoparticles were deposited on graphite-like carbon nitride via a chemical reduction approach. The result showed that the sensor had an excellent electrochemical

130

Functionalized Nanomaterial-Based Electrochemical Sensors

catalytic activity for phenol oxidation, which was contributed to the suitable conductivity and high catalytic activity of platinum nanoparticles. Under the optimum condition, the electrochemical sensor displayed a linear range of 2–20 μM and a detection limit of 0.667 μM [75]. Veerakumar et  al. developed a selective and sensitive electrochemical sensor to detect some toxic metal ions, including Cd2 +, Pb2 +, Cu2 +, and Hg2 +-based glassy carbon electrode modified with palladium nanoparticles-embedded porous activated carbons nanocomposites (Fig. 7.5). The synthesized nanocomposite proposed an excellent sensing platform for sensitive and selective metal ions detection, which is attributed to the uniformly dispersed palladium nanoparticles embedded on the porous activated carbons. For simultaneous detection of Cd2 +, Pb2 +, Cu2 +, and Hg2 +, a linear

Fig. 7.5  Schematic illustration of the palladium nanoparticles-embedded porous activated carbon nanocomposite application for detection of toxic heavy metals [76]. From P. Veerakumar, V. Veeramani, S.M. Chen, R. Madhu, S. Bin Liu, Palladium nanoparticle incorporated porous activated carbon: electrochemical detection of toxic metal ions, ACS Appl. Mater. Interfaces 8 (2016) 1319–1326.

Noble metals and nonnoble metal oxides based electrochemical sensors131

response in the ion concentration range of 0.5–5.5, 0.5–8.9, 0.5–5.0, and 0.24–7.5 μM with detection limit of 41, 50, 66, and 54 nM, respectively, was obtained [76]. Zare and Naser-Sadrabadi designed a copper and palladium nanoparticle-modified recordable digital versatile disc blade as a bipolar electrode for nitrate detection. The prepared sensor displayed a linear range from 0.5 to 3500 μM with a detection limit of 0.16 μM. The sensor was successfully used to determine nitrate in agricultural soil and mineral water [77].

7.3.5.4 Medical applications Today, electrochemical sensors have received a lot of attention in medical applications due to their ease of use, ability to analyze a specific tissue, ability to deliver results quickly, low cost, and portability. Due to the ease of synthesis and functionalization of noble metal, noble metal-based electrochemical sensors are widely used in clinical applications, including infectious microorganisms and virus recognition, DNA detection, the discovery of biomarkers, cancer diagnoses, and medicine determination. In this section, we review some examples of noble metal-based electrochemical sensors that were successfully used for medical goals and tested with biological samples. Gold nanoparticles have attracted a lot of attention in the medical field due to their unique properties such as chemical stability, easy and simple synthesis methods, biocompatibility, and noninterference with biological markers. Saxena et al. developed an electrochemical immunosensor to detect triiodothyronine (T3) hormone using gold nanoparticles and anti-T3 antibodies. Proposed immunosensor exhibits a dynamic range from 1 to 500 pg mL− 1 with limit of detection of 1 pg mL− 1 [78]. Zhang and co-workers employed gold nanoparticles to develop an ultrasensitive and specific electrochemical cytosensing platform involving colloidal carbon nanospheres to detect lung cancer cells. For sensor fabrication, at first, carbon nanospheres were decorated with gold nanoparticles via a self-assembly method. Then a glassy carbon electrode was modified with this nanocomposite. The sensor showed a linear dynamic range over 4.2 × 10− 1 to 4.2 × 10− 6 cells mL− 1 with a detection limit of 14 cells mL− 1 [79]. Kannan and Radhakrishnan utilized gold nanoparticles and polypyrrole nanotubes to fabricate a novel electrochemical sensor for levodopa utilized as a drug for the medication of Parkinson’s disease. Gold nanoparticles were electrochemically deposited on the polypyrrole nanotubes. The polypyrrole nanotubes‑gold nanoparticles were coated over the glassy carbon electrode. It showed good electrochemical activity for levodopa in a concentration range from 0.1 to 6.0 μM with a detection limit of 0.075 μM [80]. Susceptible sensors based on silver nanoparticles, one of the most important groups of nanoparticles, have been shown to provide new approaches to the early detection of diseases. Hou’s group developed a modification-free electrochemical biosensor for sensitive detection of wild-type p53 protein, which is released from cancer cells following the death and destruction of tumor cells. Silver nanoparticles formed in situ on the dsDNA-modified gold electrode surface as the electroactive reporters for signal readout. The biosensor exhibited a linear range from 0.1 to 100 pM and a detection limit of 0.1 pM [81]. Yazdanparast and co-workers fabricated an ­ultrasensitive sandwich-­type biosensor to detect human breast cancer cells (MCF7) and MUC1 biomarker.

132

Functionalized Nanomaterial-Based Electrochemical Sensors

A glassy carbon electrode was modified with a nanocomposite consisting of multiwall carbon nanotubes and poly (glutamic acid). Also, related aptamers were labeled with silver nanoparticles that led to an amplified signal and increased selectivity. The sensor presented a linear response from 1.0 × 102 to 1.0 × 107 cells mL− 1 with a detection limit of 25 cells [82]. Chin et al. reported silver nanoparticles modified screen-printed carbon electrodes for Japanese Encephalitis virus antigen detection that is a type of flaviviruses and transmitted by Culex tritaeniorhynchus mosquito human. Results showed that silver nanoparticles had significantly enhanced the electrode’s conductivity by facilitating the electron transfer [83]. Also, platinum nanoparticles based electrochemical sensors have been successfully used for medical applications. Lan et al. fabricated a novel electrochemical sensor based on platinum nanoparticle-decorated reduced graphene oxide@polystyrene nanospheres as an electrochemical immunosensor for tumor marker carcinoembryonic antigen. The proposed immunosensor detected concentrations of carcinoembryonic antigen ranging from 0.05 to 70 ng mL− 1 with a detection limit of 0.01 ng mL− 1 [84]. Fu and co-workers presented a new electrochemical sensor based on multiwalled carbon nanotubes and platinum nanoparticles modified glassy carbon electrodes for simultaneous detection of homovanillic acid and vanillylmandelic acid. Multiwalled carbon nanotubes enhanced the stability and catalytic activity of platinum nanoparticles. Under optimal conditions, the dynamic ranges were 2 × 10− 7–8 × 10− 5 mol L− 1 and 5 × 10− 7–8 × 10− 5 mol L− 1, and the detection limits were obtained 8 × 10− 8 and 1.73 × 10− 7 mol L− 1 for homovanillic acid and vanillylmandelic acid, respectively [85]. Kong et  al. described the synthesis of platinum nanoparticles supported on ­nitrogen-doped reduced graphene oxide-single wall carbon nanotubes nanocomposite as a sensitive electrochemical sensor for the determination of piroxicam. The sensor exhibited a linear range of 0.02–20 μg mL− 1 with a detection limit of 5 ng mL− 1 [86]. In the following, some applications of palladium nanoparticles-based electrochemical sensors in medicine are mentioned. Zhang and co-workers employed palladium nanoparticles@ZnO-Co3O4-multiwall carbon nanotubes nanocomposites to develop an electrochemical sensor for sensitive detection of tanshinol. Palladium nanoparticles can boost the redox process toward tanshinol due to its high catalytic activity and electrical conductivity. The sensor showed two linear ranges of 0.002–0.69 and 0.69–3.75 mM with a detection limit of 0.019 μM [87]. Cincotto et al. developed an electrochemical sensor based on palladium nanoparticles supported over reduced graphene to determine desipramine that is a kind of antidepressant in urine samples. The sensor showed a linear response in the range of 0.3–2.5 μmol L− 1 with a detection limit of 1.04 nmol L− 1 [88].

7.4 Nonnoble metal oxides based electrochemical sensors Metal elements can form different types of oxide compounds with different geometric and electrical structures that can show metallic, semiconductor, or insulator features. They are widely used in various fields such as the fabrication of sensors, microelectronic circuits, fuel cells, piezoelectric devices, and as catalysts. Although noble metal

Noble metals and nonnoble metal oxides based electrochemical sensors133

and carbon-based nanomaterials are widely utilized in the construction of electrochemical sensors, metal oxide nanomaterials have recently emerged as a useful platform. Metal oxide nanoparticles that are synthesized in different methods have different properties due to their small size, high stability, and surface area. The surface modification of the working electrodes with metal oxide nanoparticles as sensing elements is done via physical adsorption, electrodeposition, chemical covalent bonding, or electropolymerization with redox polymers. Biocompatible metal oxide nanoparticles are commonly used to construct DNA sensors, immunosensors, and enzymatic sensors to immobilize biomolecules. Also, semiconductive metal oxide nanoparticles are used as markers and tracers in electrochemical sensors [89]. We start by introducing metal oxide nanoparticles’ properties and continue by investigating some critical examples of metal oxide-based electrochemical sensors applications in different fields.

7.4.1 Properties of nonnoble metal oxides Most studies have shown that metal oxide nanoparticles’ unique physical and chemical properties are largely dependent on their size. As the nanoparticles’ size decreases, the number of atoms on the surface increases, and their specific size can change their chemical, magnetic, and electronic properties. Knowing the physical and chemical properties of nanomaterials is critical to their application in industry as sensors, ceramics, adsorbents, and catalysts. In fact, the many applications of metal oxide nanoparticles have attracted interest from researchers in various fields, including agriculture, biomedical, catalysis, chemistry, energy, electronics, environment, information technology, medicine, optical, and sensing [90]. Metal oxides are widely used in catalysis and absorption because of their acid/base and redox properties. The redox properties, the coordination environment of surface atoms, and the oxidation state at surface layers are essential features for their application as catalysts or absorbents. Most people think that metal oxide nanoparticles are incredibly stable, but these materials could dissolve even in biological environments, depending on their solubility and ligand. For example, research has shown that ZnO, CuO, WO3, NiO, Sb2O3, and CoO dissolve in the cell culture medium. However, by adjusting the pH or ligands’ presence, the dissolution can be controlled [91]. Controlled dissolution is significant for designing sensors. Iron oxides (Fe2O3 and Fe3O4) nanoparticles are widely used in electrochemical sensor fabrication. The oxidation state of Fe in Fe2O3 is + 3 and in Fe3O4 is + 2 and + 3, which has caused higher electrical conductivity of Fe3O4 due to the electron hopping processes between the Fe2 + and Fe3 +. Incorporating iron oxide nanoparticles with metals such as Au, Ag, Zr, and Co creates core-shell bimetallic structures that increase efficiency because of their synergistic effect [92]. Also, iron oxide nanoparticles are utilized as effective electrocatalysts when doped with some metals like Ba [93], Ni [94], Co [95], and Pd-Pt [96]. Moreover, iron oxide nanoparticles combine with carbon nanomaterials such as carbon nanotubes and graphene oxide as support that prevents agglomeration, enhances the surface to volume ratio, and exhibits excellent electrocatalytic activity for various analytes [89]. Other useful nanomaterials for electrode materials in electrochemical sensors are different forms of manganese

134

Functionalized Nanomaterial-Based Electrochemical Sensors

oxide nanoparticles like MnO, MnO2, and Mn3O4. These metal oxides are nontoxic, low cost, environmentally friendly, and naturally available. These materials are widely used in biosensing, catalysis, energy storage, molecular adsorption, and ion exchange [97]. Titanium dioxide (TiO2) nanoparticles are one of the preferred materials in electrochemical sensing due to their high conductivity, low cost, and biocompatibility. TiO2 is chemically stable in both acidic and alkaline solutions and acts as an effective catalyst for reducing many organic molecules [98]. The main problem in the fabrication of electrochemical sensors based on TiO2 nanoparticles is the low solubility of these nanoparticles and their instability on the electrode surface, which reduces the sensitivity. Fortunately, this problem can be solved by modifying the electrode surface with enzymes or noble metal nanoparticles. Copper oxide nanoparticles (CuO and Cu2O) are the most widely used nanoparticles in the manufacture of electrochemical sensors. These metal oxides are also widely utilized in other fields, such as catalysis, lithium-ion batteries, gas sensors, solar energy, and optical devices. When copper oxide nanoparticles with carbon materials such as mesoporous carbons [99], carbon nanotubes [100], carbon nanofibers [101], and graphene [102] are used to fabricate electrochemical sensors, the sensor’s performance improves due to improved charge transfer between the analyte and the matrix. Among the metal oxide nanoparticles, zinc oxide (ZnO) nanoparticles have attracted special attention. ZnO properties include biocompatibility, nontoxicity, low-cost synthesis, high electrochemical activity, chemical stability, and so on. One of the problems with electrochemical sensors based on ZnO nanoparticles the removal of these nanoparticles from the surface of the electrode during functionalization. This problem has been solved by combining carbon nanotubes with these nanoparticles. ZnO also has shown excellent properties when combined with other nanoparticles. For example, gold nanoparticles-ZnO composite has interesting properties, including high chemical stability, optical sensitivity, high catalytic activity, and biocompatibility [103]. Another group of metal oxide nanoparticles is zirconia nanoparticles (ZrO2), which play an important role in constructing electrochemical sensors due to their unique properties like affinity for the groups containing oxygen, chemical inertness, biocompatibility, and thermal stability. On the other hand, ZrO2 is widely utilized as a capturing agent in the fabrication of electrochemical sensors for selective detection of phosphorylated proteins and organophosphate pesticides because of its strong affinity with the phosphoric group [104]. Cobalt oxide (CoOx) nanoparticles have attracted enormous attention in electrochemical sensing because of their excellent stability and great activity. The sensors used to detect temperature and humidity are often based on CoOx [105]. Common synthesis methods for CoOx nanoparticle are hydrothermal [106], chemical method [107], heating cobalt foil [108], calcination [109], and electrodeposition method [110]. Nickel oxide (NiO) nanoparticles are another group of metal oxide that, due to their high catalytic activity, low price, low toxicity, and good stability, are widely used in the fabrication of electrochemical biosensors [111]. Tungsten oxide (WO3) is considered an n-type semiconductor and has a bandgap of approximately 2.5 eV. WO3 nanoparticles are the most attractive candidates for sensors because of the high surface-to-­ volume ratio. Moreover, WO3 is widely used in gas-sensing, solar-powered water splitting, dye photodegradation, and smart windows due to its unique photocatalytic,

Noble metals and nonnoble metal oxides based electrochemical sensors135

electrochromic, and photochromic properties [112]. Due to the simultaneous presence of different oxidation states of vanadium and unique layered structure, vanadium oxide has wide application in sensors, lithium-ion batteries, and supercapacitor. Vanadium (V) oxide (V2O5) is the most stable and common form of vanadium oxide. V2O5 acts as a mediator in many electrocatalytic reactions because it exhibits considerable redox behavior (V5 +/4 +) [89].

7.4.2 Application of nonnoble metal oxides based electrochemical sensors Over the last couple of decades, electrochemical sensors based on nonnoble metal oxides have drawn remarkable interest due to their wide range of applications in various fields such as environment, medicine, and food quality control. In this section, we examine examples of the use of these sensors in different fields. Maleki and co-authors reported an electrochemical sensor based on Fe3O4 nanoparticles for simultaneous detection of Pb2 + and Cd2 + ions in environmental waters (river water, wastewater, and lake water). For sensor fabrication, a carbon paste electrode was modified with Fe3O4@polyamidoamine dendrimer nanocomposite. The proposed sensor exhibited excellent performance for multielement detection because of the high adsorption ability and a high surface-to-volume ratio of the Fe3O4@polyamidoamine dendrimer nanocomposite. The prepared sensor showed a linear response to Pb2 + and Cd2 + over a concentration range from 0.5 to 80 ng mL− 1. Detection limits for Pb2 + and Cd2 + were obtained 0.17 ng mL− 1 and 0.21 ng mL− 1, respectively [113]. El-badawy et  al. developed a novel and simple electrochemical sensor based on carbon paste electrode modified with MnO2 nanoparticles-reduced graphene oxide to determine the antihepatitis C daclatasvir in its Daclavirocyrl tablets, urine, and serum. It successfully detected antihepatitis C daclatasvir in a linear dynamic range of 1.0–200 nM, with a good LOD of 1.25 × 10− 10 M [114]. A carbon paste-based electrode was modified with TiO2 nanoparticles/graphene oxide nanosheets for the simultaneous determination of benzocaine and antipyrine in oral fluid (saliva) and pharmaceutical products. The prepared sensor showed linear ranges from 1.0 × 10− 6 to 1.0 × 10− 4 M and 1.2 × 10− 8 to 8.0 × 10− 5 M for benzocaine and antipyrine, respectively [115]. Pourbeyram et al. reported CuO nanoparticles’ formation decorated reduced graphene oxide on pencil graphite electrode as a nonenzymatic sensor for glucose detection. The linear range of detection was 0.1–150 μM, with a detection limit of 0.09 μM [116]. An electrochemical sensor was fabricated using a glassy carbon electrode modified with ZnO nanoparticles to detect 1,3-dimethyl xanthine in pharmaceutical and urine samples. Linear rang was obtained from 1.0 × 10− 6 to 2.0 × 10− 5 M with a detection limit of 1.03 × 10− 8 μM [117]. Zhao co-workers prepared an electrochemical sensor based on nitrogen-doped carbon sheets embedded with ZrO2 nanoparticles to detect methyl parathion (Fig.  7.6). The embedded ZrO2 nanoparticles in nitrogen-doped carbon sheets led to a strong affinity toward the phosphorus groups’ methyl parathion molecules. The sensor provided a linear range of parathion analysis of 0.01–15 μg mL− 1, with a detection limit of 0.115 ng mL− 1 [118]. A Co3O4-NiO nanoparticles-based electrochemical sensor was deployed to detect glucose. This sensor was fabricated by

136

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 7.6  Synthesis process of the bio-derived nitrogen-doped carbon sheets embedded with ZrO2 nanoparticles to determine methyl parathion [118]. From H. Zhao, B. Liu, Y. Li, B. Li, H. Ma, S. Komarneni, One-pot green hydrothermal synthesis of bio-derived nitrogen-doped carbon sheets embedded with zirconia nanoparticles for electrochemical sensing of methyl parath, Ceram. Int. 46 (2020) 19713–19722.

modifying a glassy carbon electrode with multiwall carbon nanotubes/ionic liquid/ graphene quantum dots nanocomposite and Co3O4-NiO nanoparticles. The sensor showed two linear ranges from 1.0 to 190.0 μM and 190.0 to 4910 μM, with a low detection limit of 0.3 μM [40]. Alizadeh’s group reported a novel electrochemical sensor for cancer cell detection using CuO/WO3 nanoparticle decorated graphene oxide nanosheet. The sensor offered cancer cell detection within a linear range of 50–105 cells mL− 1 and a detection limit of 18 cells mL− 1 [119].

7.5 Conclusion One of the essential areas of chemistry research is the electrochemical sensing field. The integration of nanotechnology and electrochemistry has led to significant progress in the fabrication of electrochemical sensors. Novel electrochemical sensors fabricated on noble metal and nonnoble metal oxide show high sensitivity and excellent

Noble metals and nonnoble metal oxides based electrochemical sensors137

selectivity when conjugated to biorecognition molecules. Electrochemical sensors based on noble metals and nonnoble metal oxides proposed an appropriate analytical tool because of the fast, precise, and accurate analytes’ monitoring. In this chapter, different methods of nanoparticle synthesis were thoroughly investigated. Also, the properties and characteristics of noble metal nanoparticles and nonnoble metal oxide nanoparticles were expressed. Finally, various noble metals applications, nonnoble metal oxides-based electrochemical sensors in different fields such as medicine, environment, and food quality, have been discussed.

References [1] A. Chen, S. Chatterjee, Chem. Soc. Rev. 42 (2013) 5425–5438. [2] Z. Meng, R.M. Stolz, L. Mendecki, K.A. Mirica, Chem. Rev. 119 (2019) 478–598. [3] W. Siangproh, W. Dungchai, P. Rattanarat, O. Chailapakul, Anal. Chim. Acta 690 (2011) 10–25. [4] F. Wang, S. Hu, Microchim. Acta 165 (2009) 1–22. [5] X. Luo, A. Morrin, A.J. Killard, M.R. Smyth, Electroanalysis 18 (2006) 319–326. [6] X.L. Luo, J.J. Xu, W. Zhao, H.Y. Chen, Biosens. Bioelectron. 19 (2004) 1295–1300. [7] N. Baig, M. Sajid, T.A. Saleh, TrAC Trends Anal. Chem. 111 (2019) 47–61. [8] L. Zhang, J. Wang, Y. Tian, Microchim. Acta 181 (2014) 1471–1484. [9] S. Kempahanumakkagari, A. Deep, K.H. Kim, S. Kumar Kailasa, H.O. Yoon, Biosens. Bioelectron. 95 (2017) 106–116. [10] K. Murtada, V. Moreno, J. Electroanal. Chem. 861 (2020) 113988. [11] V. Pareek, A. Bhargava, R. Gupta, N. Jain, J. Panwar, Adv. Sci. Eng. Med. 9 (2017) 527–544. [12] J. Chen, P. Mela, M. Möller, M.C. Lensen, ACS Nano 3 (2009) 1451–1456. [13] G. Walters, I.P. Parkin, J. Mater. Chem. 19 (2009) 574–590. [14] C. Zhu, D. Du, A. Eychmüller, Y. Lin, Chem. Rev. 115 (2015) 8896–8943. [15] F. Mafuné, J.Y. Kohno, Y. Takeda, T. Kondow, H. Sawabe, J. Phys. Chem. B 104 (2000) 9111–9117. [16] M.C. Daniel, D. Astruc, Chem. Rev. 104 (2004) 293–346. [17] J. Turkevich, P.C. Stevenson, J. Hillier, Discuss. Faraday Soc. 11 (1951) 55–75. [18] P.C. Lee, D. Meisel, J. Phys. Chem. 86 (1982) 3391–3395. [19] J. Zhang, J. Fang, J. Am. Chem. Soc. 131 (2009) 18543–18547. [20] N. Jain, A. Bhargava, J.C. Tarafdar, S.K. Singh, J. Panwar, Appl. Microbiol. Biotechnol. 97 (2013) 859–869. [21] M.A.L. Quintela, Curr. Opin. Colloid Interface Sci. 8 (2003) 145–155. [22] J. Zhu, X.l. Jin, Superlattice. Microst. 41 (2007) 271–276. [23] R.A. Khaydarov, R.R. Khaydarov, O. Gapurova, Y. Estrin, T. Scheper, J. Nanopart. Res. 11 (2009) 1193–1200. [24] C. Li, T. Sato, Y. Yamauchi, Angew. Chemie 125 (2013) 8208–8211. [25] L. Gu, N. Luo, G.H. Miley, J. Power Sources 173 (2007) 77–85. [26] X. Lu, F. Luo, H. Song, S. Liao, H. Li, J. Power Sources 246 (2014) 659–666. [27] Y. Zhao, S.J. Qin, Y. Li, F.X. Deng, Y.Q. Liu, G.B. Pan, Electrochim. Acta 145 (2014) 148–153. [28] N. Tian, Z.Y. Zhou, S.G. Sun, Chem. Commun. 12 (2009) 1502–1504.

138

Functionalized Nanomaterial-Based Electrochemical Sensors

[29] F. Cheng, H. Wang, Z. Sun, M. Ning, Z. Cai, M. Zhang, Electrochem. Commun. 10 (2008) 798–801. [30] B.J. Plowman, S.K. Bhargava, A.P. O’Mullane, Analyst 136 (2011) 5107–5119. [31] S. Choi, H. Jeong, K.H. Choi, J.Y. Song, J. Kim, ACS Appl. Mater. Interfaces 6 (2014) 3002–3007. [32] R.R. Mishra, P. Chandran, S.S. Khan, RSC Adv. 4 (2014) 51787–51793. [33] A. Waheed, M. Mansha, N. Ullah, TrAC Trends Anal. Chem. 105 (2018) 37–51. [34] G. Maduraiveeran, W. Jin, Trends Environ. Anal. Chem. 13 (2017) 10–23. [35] B. Wolfrum, E. Katelhon, A. Yakushenko, K.J. Krause, N. Adly, M. Huske, P. Rinklin, Acc. Chem. Res. 49 (2016) 2031–2040. [36] S. Guo, E. Wang, Nano Today 6 (2011) 240–264. [37] E. Lebegue, C.M. Anderson, J.E. Dick, L.J. Webb, A.J. Bard, Langmuir 31 (2015) 11734–11739. [38] M.R. Mahmoudian, W.J. Basirun, Y. Alias, RSC Adv. 6 (2016) 36459–36466. [39] G.H. Wu, Y.F. Wu, X.W. Liu, M.C. Rong, X.M. Chen, X. Chen, Anal. Chim. Acta 745 (2012) 33–37. [40] P. Nasr-Esfahani, A.A. Ensafi, B. Rezaei, Electroanalysis 31 (2019) 40–49. [41] A.S. Shamsabadi, H. Tavanai, M. Ranjbar, A. Farnood, M. Bazarganipour, Mater. Today Commun. 24 (2020) 100963. [42] J. Xu, T. Chen, X. Qiao, Q. Sheng, T. Yue, J. Zheng, Colloids Surf. A Physicochem. Eng. Asp. 561 (2019) 25–31. [43] A.K. Mishra, B. Mukherjee, A. Kumar, D.K. Jarwal, S. Ratan, C. Kumar, S. Jit, RSC Adv. 9 (2019) 1772–1781. [44] M.A. Deshmukh, B.C. Kang, T.J. Ha, J. Mater. Chem. C 8 (2020) 5112–5123. [45] M. Usman, L. Pan, A. Farid, A.S. Khan, Z. Yongpeng, M.A. Khan, M. Hashim, Carbon 157 (2020) 761–766. [46] N. Khalaf, T. Ahamad, M. Naushad, N. Al-hokbany, S.I. Al-Saeedi, S. Mutehri, S.M. Alshehri, Int. J. Biol. Macromol. 146 (2020) 763–772. [47] A.A. Ensafi, N. Zandi-Atashbar, B. Rezaei, M. Ghiaci, M.E. Chermahini, P. Moshiri, RSC Adv. 6 (2016) 60926–60932. [48] Y. Zhu, X. Zhang, J. Sun, M. Li, Y. Lin, K. Kang, Y. Meng, Z. Feng, J. Wang, Microchim. Acta 186 (2019), 538. [49] L.T. Hoa, K.G. Sun, S.H. Hur, Sens. Actuators B Chem. 210 (2015) 618–623. [50] C. Su, C. Zhang, G. Lu, C. Ma, Electroanalysis 22 (2010) 1901–1905. [51] N. Shishegari, A. Sabahi, F. Manteghi, A. Ghaffarinejad, Z. Tehrani, J. Electroanal. Chem. 871 (2020) 114285. [52] M. Wang, Z. Ma, J. Li, Z. Zhang, B. Tang, X. Wang, J. Colloid Interface Sci. 511 (2018) 355–364. [53] M. Zhang, Y. Liu, J. Wang, J. Tang, Microchim. Acta 186 (2019) 1–8. [54] W. Liu, H. Zhang, B. Yang, Z. Li, L. Lei, X. Zhang, J. Electroanal. Chem. 749 (2015) 62–67. [55] N. Jia, B. Huang, L. Chen, L. Tan, S. Yao, Sens. Actuators B Chem. 195 (2014) 165–170. [56] X. Yang, Y. Ouyang, F. Wu, Y. Hu, Y. Ji, Z. Wu, Sens. Actuators B Chem. 238 (2017) 40–47. [57] J. Narang, N. Chauhan, C.S. Pundir, Analyst 136 (2011) 4460–4466. [58] J. Ma, W. Bai, J. Zheng, Microchim. Acta 186 (2019) 1–8. [59] E. Aparicio-Martinez, A. Ibarra, I.A. Estrada-Moreno, V. Osuna, R.B. Dominguez, Sens. Actuators B Chem. 301 (2019) 127101. [60] M. Gholami, B. Koivisto, Appl. Surf. Sci. 467 (2019) 112–118.

Noble metals and nonnoble metal oxides based electrochemical sensors139

[61] R. Zalnėravicius, A. Gedminas, T. Ruzgas, A. Jagminas, J. Electroanal. Chem. 839 (2019) 274–282. [62] R. Jimenez-Perez, J. Gonzalez-Rodriguez, M.I. Gonzalez-Sanchez, B. GomezMonedero, E. Valero, Sens. Actuators B Chem. 298 (2019) 126878. [63] B. Thirumalraj, R. Sakthivel, S.M. Chen, C. Rajkumar, L.K. Yu, S. Kubendhiran, Microchem. J. 146 (2019) 673–678. [64] M. Baghayeri, H. Alinezhad, M. Tarahomi, M. Fayazi, M. Ghanei-Motlagh, B. Maleki, Appl. Surf. Sci. 478 (2019) 87–93. [65] M. Guler, Y. Dilmac, J. Electroanal. Chem. 834 (2019) 49–55. [66] L. Bu, Q. Xie, H. Ming, J. Alloys Compd. 823 (Iii) (2020) 153723. [67] X. Qin, et al., Int. J. Electrochem. Sci. 15 (2) (2020) 1517–1528. [68] M. Shamsipur, Z. Karimi, M. Amouzadeh Tabrizi, Microchem. J. 133 (2017) 485–489. [69] Z. Bo, T. Zhibo, Int. J. Electrochem. Sci. 15 (2020) 6177–6187. [70] E. Eksin, A. Erdem, T. Fafal, B. Kıvcak, Electroanalysis 31 (2019) 1075–1082. [71] D. Ning, H. Zhang, J. Zheng, J. Electroanal. Chem. 717 (2014) 29–33. [72] G. Pan, J. Chen, J. Guang, Int. J. Electrochem. Sci. 11 (2016) 5952–5961. [73] F. Laghrib, H. Houcini, F. Khalil, A. Liba, M. Bakasse, S. Lahrich, M.A. El Mhammedi, ChemistrySelect 5 (2020) 1220–1227. [74] Q. Sheng, D. Liu, J. Zheng, J. Electroanal. Chem. 796 (2017) 9–16. [75] B.B. Song, Y.F. Zhen, H.Y. Yin, X.C. Song, J. Nanosci. Nanotechnol. 19 (2019) 4020–4025. [76] P. Veerakumar, V. Veeramani, S.M. Chen, R. Madhu, S. Bin Liu, ACS Appl. Mater. Interfaces 8 (2016) 1319–1326. [77] A. Naser-Sadrabadi, H.R. Zare, Microchem. J. 148 (2019) 206–213. [78] R. Saxena, H. Fouad, S. Srivastava, J. Nanosci. Nanotechnol. 20 (2020) 6057–6062. [79] H. Zhang, H. Ke, Y. Wang, P. Li, C. Huang, N. Jia, Microchim. Acta 186 (2019) 2–8. [80] A. Kannan, S. Radhakrishnan, Mater. Today Commun. 25 (2020) 101330. [81] L. Hou, Y. Huang, W. Hou, Y. Yan, J. Liu, N. Xia, Int. J. Biol. Macromol. 158 (2020) 580–586. [82] S. Yazdanparast, A. Benvidi, M. Banaei, H. Nikukar, M.D. Tezerjani, M. Azimzadeh, Microchim. Acta 185 (2018) 1–10. [83] S.F. Chin, L.S. Lim, H.C. Lai, S.C. Pang, M. Sia, H. Sum, D. Perera, Nano Biomed. Eng. 11 (2019) 333–339. [84] Q. Lan, C. Ren, A. Lambert, G. Zhang, J. Li, Q. Cheng, X. Hu, Z. Yang, ACS Sustain. Chem. Eng. 8 (2020) 4392–4399. [85] B. Fu, H. Chen, Z. Yan, Z. Zhang, J. Chen, T. Liu, K. Li, J. Electroanal. Chem. 866 (2020) 114165. [86] F.Y. Kong, R.F. Li, L. Yao, Z.X. Wang, W.X. Lv, W. Wang, J. Electroanal. Chem. 832 (2019) 385–391. [87] C. Zhang, J. Ren, Y. Xing, M. Cui, N. Li, P. Liu, X. Wen, M. Li, Mater. Sci. Eng. C 108 (2020) 110214. [88] F.H. Cincotto, D.L.C. Golinelli, S.A.S. Machado, F.C. Moraes, Sens. Actuators B Chem. 239 (2017) 488–493. [89] J.M. George, A. Antony, B. Mathew, Microchim. Acta 185 (2018) 2753. [90] M.S. Chavali, M.P. Nikolova, SN Appl. Sci. 1 (2019) 5547. [91] H. Fan, Z. Zhao, G. Yan, X. Zhang, C. Yang, H. Meng, Z. Chen, H. Liu, W. Tan, Angew. Chemie Int. Ed. 54 (2015) 4801–4805. [92] M. Arvand, S. Orangpour, N. Ghodsi, RSC Adv. 5 (2015) 46095–46103.

140

Functionalized Nanomaterial-Based Electrochemical Sensors

[93] N.S.E. Osman, N. Thapliyal, W.S. Alwan, R. Karpoormath, T. Moyo, J. Mater. Sci. Mater. Electron. 26 (2015) 5097–5105. [94] S.X. Luo, Y.H. Wu, H. Gou, Y. Liu, Adv. Mater. Res. 850 (2014) 1279–1282. [95] X. Cui, Y.Q. Sun, R. Ma, X.C. Song, Adv. Mater. Res. 941 (2014) 377–380. [96] X. Sun, S. Guo, Y. Liu, S. Sun, Nano Lett. 12 (2012) 4859–4863. [97] J. Zhang, W. Chu, J. Jiang, X.S. Zhao, Nanotechnology 22 (2011) 1–10. [98] R. Hallaj, N. Haghighi, Microchim. Acta 184 (2017) 3581–3590. [99] J. Zhang, C. Wang, Y. Tang, H. Peng, Z.C. Ye, C.C. Li, T.Q. Lou, Nephrology 18 (2013) 125–131. [100] N. Quoc Dung, D. Patil, H. Jung, D. Kim, Biosens. Bioelectron. 42 (2013) 280–286. [101] J. Zhang, Y.L. Song, C.X. Bai, Int. J. COPD 8 (2013) 433–438. [102] Y.W. Hsu, T.K. Hsu, C.L. Sun, Y.T. Nien, N.W. Pu, M. Der Ger, Electrochim. Acta 82 (2012) 152–157. [103] S.K. Mehta, K. Singh, A. Umar, G.R. Chaudhary, S. Singh, Electrochim. Acta 69 (2012) 128–133. [104] Y. Wang, J. Jin, C. Yuan, F. Zhang, L. Ma, D. Qin, D. Shan, X. Lu, Analyst 140 (2015) 560–566. [105] H. Heidari, E. Habibi, Microchim. Acta 183 (2016) 2259–2266. [106] T.T. Nguyen, V.H. Nguyen, R.K. Deivasigamani, D. Kharismadewi, Y. Iwai, J.J. Shim, Solid State Sci. 53 (2016) 71–77. [107] M.M. Shahid, P. Rameshkumar, A. Pandikumar, H.N. Lim, Y.H. Ng, N.M. Huang, J. Mater. Chem. A 3 (2015) 14458–14468. [108] W. Jia, M. Guo, Z. Zheng, T. Yu, E.G. Rodriguez, Y. Wang, Y. Lei, J. Electroanal. Chem. 625 (2009) 27–32. [109] L.A. Saghatforoush, S. Sanati, M. Hasanzadeh, Res. Chem. Intermed. 41 (2015) 4361–4372. [110] A. Salimi, R. Hallaj, H. Mamkhezri, S.M.T. Hosaini, J. Electroanal. Chem. 619–620 (2008) 31–38. [111] G. Zeng, W. Li, S. Ci, J. Jia, Z. Wen, Sci. Rep. 6 (2016) 1–8. [112] O. Tovide, N. Jaheed, N. Mohamed, E. Nxusani, C.E. Sunday, A. Tsegaye, R.F. Ajayi, N. Njomo, H. Makelane, M. Bilibana, P.G. Baker, A. Williams, S. Vilakazi, R. Tshikhudo, E.I. Iwuoha, Electrochim. Acta 128 (2014) 138–148. [113] B. Maleki, M. Baghayeri, M. Ghanei-Motlagh, F.M. Zonoz, A. Amiri, F. Hajizadeh, A. Hosseinifar, E. Esmaeilnezhad, Measurement 140 (2019) 81–88. [114] F.M. El-badawy, M.A. Mohamed, H.S. El-Desoky, Microchem. J. 157 (2020) 104914. [115] M.A. Mohamed, S.A. Atty, H.A. Merey, T.A. Fattah, C.W. Foster, C.E. Banks, Analyst 142 (2017) 3674–3679. [116] S. Pourbeyram, J. Abdollahpour, M. Soltanpour, Mater. Sci. Eng. C 94 (2019) 850–857. [117] A.B. Bandi, N.P. Shetti, S.J. Malode, S.D. Bukkitgar, R.M. Kulkarni, Mater. Today Proc. 18 (2019) 590–595. [118] H. Zhao, B. Liu, Y. Li, B. Li, H. Ma, S. Komarneni, Ceram. Int. 46 (2020) 19713–19722. [119] N. Alizadeh, A. Salimi, R. Hallaj, F. Fathi, F. Soleimani, Mater. Sci. Eng. C 99 (2019) 1374–1383.

Section E Functionalized nanomaterialbased electrochemical based sensors for environmental applications

This page intentionally left blank

Functionalized nanomaterialbased environmental sensors: An overview

8

Ali A. Ensafia,b, N. Kazemifarda, and Z. Saberia a Department of Chemistry, Isfahan University of Technology, Isfahan, Iran, bDepartment of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States

8.1 Introduction In the last decades, human society’s development in the fields of transportation, energy, communications, and production of numerous commodities have a tight connection with some considerable changes in the quality of the environment in particular terms of atmosphere, soil, and water pollution [1]. The monitoring of hazardous contaminants is significant to keep the ecosystems and human health from probable damages of inorganic and organic pollutants [2]. New law and equipment are applied for online pollutants monitoring, for instance, (i) quality monitoring of wastewater to prevent the discharge of detergents or synthetic drug residues and (ii) Control of carcinogens and explosives discharged into the environment continuously [3]. The most important contaminants in water, soil, and air can be classified as pesticides, heavy metals, detergents, and gas species with polluting effects summarized in the following. Pesticides are a class of compounds including insecticides, herbicides, fungicides, nematodes, and rodenticides that can be classified into organophosphorus, neonicotinoids, organochlorines, organophosphates, carbamates, and pyrethroids. They have been extensively consumed in agricultural and industrial areas to remove, control, and kill harmful diseases, insects, fungi, weeds, and pests [4–6]. The degradation of many pesticides is severe and can be accumulated in animals. The widespread use of pesticides has a negative influence on human health and the natural environment. Millions of people worldwide suffer from acute pesticide-related health effects from agricultural products contaminated with pesticides every year. To reduce the toxic effects and bioaccumulation of pesticides in the ecosystems, measuring trace levels and dose adjustment are necessary. Thus, the improvement of current methods and the development of new techniques is essential for simple pesticide measurement at low concentrations [6]. Inorganic species include nonmetallic (anions: NO3−, NH4+, CN−, NO2−, and molecules: toxic gases like H2S, SO2, NOx) and toxic metallic (heavy metals) analytes [7]. The levels of nitrogenous inorganic contaminants (e.g., nitrite, ammonium, and nitrate) are raised in the water body due to the waste of agricultural fields and industrial/municipal release sewerage. Reaction nitrite with secondary amines in the human body can cause the formation of carcinogenic nitrosamine, leading to liver Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00020-X Copyright © 2022 Elsevier Ltd. All rights reserved.

144

Functionalized Nanomaterial-Based Electrochemical Sensors

and ­gastrointestinal cancers. Also, elevated ammonia levels in the body may lead to convulsion, coma, and even death [8]. Major sources of H2S, SO2, CO, NOx, and CO2 that are primary urban pollutants are industrial activities and transportation. Air pollution is a serious problem in the past decades that is connected with the intense economic development of densely populated and industrialized societies. The monitoring of these gaseous pollutant concentrations accurately and ideally in situ is a challenging priority because of their mortal result on the environment, industrial safety, and human health [9,10]. Therefore, the development of a noble technique is vital in real time, in situ detection of contaminants in a fast and accurate method. Heavy metals, like other pollutants, demonstrate a rising environmental and health problem [11]. Although they are naturally found through pedogenetic and biogeochemical processes, large amounts of heavy metals in the environment result from anthropogenic activities: smelting operations, petroleum combustion, nuclear power stations waste incineration, and wastes from mining, industrial, and agricultural uses. They can remain in the environment for decades or even centuries because they cannot be biodegradable [12,13]. The metallic elements like lead (Pb), arsenic (As), mercury (Hg), chromium (Cr), and cadmium (Cd) are instances of heavy metal that are found to be very dangerous to human health even in trace amounts. Also, severe diseases can result in long-dated or chronic high-level contact, such as organs or nervous system problems, cancers, and even death. In addition to the direct impact on health or the environment, significant economic and financial damage can occur through water or soil contaminations. Inorganic pollutants such as heavy metals and anions such as nitrates and nitrites, etc., are not easily destroyed in the environment and are more present in nature. So, the need for determination of deficient concentrations led to developing new methods [14,15]. Any component that can be applied as a cleaning agent is known as “detergent.” Detergents are organic compounds that are usually applied in industrial and domestic uses [16]. Detergents are classified into two types with different characteristics: phosphate detergents and surfactant detergents. The defective degradation of surfactants leads to a layer of foam on the surface of streams and rivers that decrease the rate of oxygen penetration from air into water and result in incomplete absorption of dissolved oxygen by aquatic organisms. The phosphate-based detergents that enter into water cause the extreme growth of algae. In addition to the above-mentioned problems, waters contaminated by phosphates and surfactant detergents are toxic for humans. Control and determination of the amount of detergents are critical that need rapid, sensitive, inexpensive methods [17,18]. To evaluate the environmental pollutants, the development of sensitive, selective, simple, and trustworthy analytical approaches is crucial. Compared to conventional methods used in measuring pollutants, including chromatography and mass spectrometry, electrochemical methods have significant advantages, including the need for simpler and cheaper equipment, high sensitivity, accessibility to miniaturized, user-friendly, remote sensing capability, and portability [19]. Another distinct property of electrochemical systems is detecting a broad range of compounds from inorganic, organic, ionic molecules to metal ions.

Functionalized nanomaterial-based for environmental sensors

145

Analytical data as electrical signals result from interaction with the target analytes with the layer of recognition at the sensing electrode. Electrochemical systems can be classified into some categories according to the kind of electrical signal, including potentiometric, voltammetric, and amperometric techniques [20]. Various electrochemical sensors have been designed for environmental pollutants monitoring based on analyte type, properties of the sample matrix, and the sensitivity or selectivity aspects for sensing assay [3]. Fig. 8.1 shows the response mechanism of an electrochemical sensor. Nanomaterials have attracted attention due to unique electrical, chemiphysical characteristics, such as high specific surface area, high adsorption capacity, and reactive capability, and other interesting features that can only be seen on the nanoscale, not on the bulk [21]. The coupling of nanomaterials with electrochemical systems introduces reliable and robust electrical devices for effective analysis and pollution control. During the last decades, electrochemical sensors and biosensors made by nanomaterials have enormously been used as powerful analytical techniques for the manifold of environmental monitoring applications by numerous advantages such as high sensitivity, effective catalysis, cost-effective, and quick mass transport [22]. Different nanomaterials can be classified by chemical composition into four categories: (i) Noble metals; (ii) Metal oxides; (iii) Carbon nanomaterials; (iv) Polymer nanomaterials [1]. Fig.  8.2 displays the schematic illustration of the nanomaterials used in electrochemical sensors for environmental monitoring. The nanostructure materials can be produced via various strategies containing physical methods (for example, laser ablation, physical vapor deposition, and flash spray pyrolysis), chemical methods (for instance, sol-gel processes, hydrothermal method, thermal decomposition, and chemical vapor deposition), photochemical procedures

Fig. 8.1  The response mechanism of an electrochemical sensor.

146

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 8.2  Schematic illustration of the nanomaterials used in electrochemical sensor for environmental monitoring [1]. From G. Maduraiveeran, W. Jin, Nanomaterials based electrochemical sensor and biosensor platforms for environmental applications, Trends Environ. Anal. Chem. 13 (2017) 10–23.

(such as photodeposition) and electrochemical methods (such as electrodeposition, anodic, and cationic oxidation) [23,24]. The use of nanomaterials to modify the electrode enhances the signal by increasing the electrode’s conductivity and the catalytic property of the electrode. With the use of nanomaterials, the interaction of reagents increases, and besides, with the stabilization of the considered functional groups on the nanomaterials, the system’s selectivity increases [25]. This chapter overviews the latest advances in the development of electrochemical procedures with different nanomaterials for sensitive and quick detection of various contaminants existing in the environment. The electrochemical sensors applied to measure environmental pollutants are classified according to the nanoparticles used, like noble metal nanostructures, metal oxide nanomaterials, carbon nanoparticles, and polymer nanoparticles. The advantages and drawbacks of these techniques are summarized. Because there were so many papers in this field, it was not possible to summarize and review all of them in this chapter; some of them are listed in Table 8.1, and only a limited number of them, that are more attractive and innovative, have been investigated in more details in this chapter.

Table 8.1  Application of various nanomaterials in the measurement of environmental pollutants. Nanomaterial

Pollutant

Method

Linear range

Detection limit

Ref.

Cr (VI) Cr (VI)

CV Amperometry

100–1500 ppb 4 × 10− 3–5.7 × 10− 2 M

4.3 ppb 2 × 10− 3 M

[26] [27]

Cd(II)

SWASV

0.5–40 ppb

0.100 ppb

[28]

Pb(II)

SWASV

0.5–40 ppb

0.05 ppb

[28]

Heavy metals Polycrystalline gold AuNPs on thiol functionalized silicate network AuNPs-graphene-cysteine composite modified bismuth AuNPs-graphene-cysteine composite modified bismuth AuNPs modified screenprinted carbon arrays AuNPs-doped carbon foams TiO2/Ti+ 3 ion Phytic acid/polypyrrole/GO TiO2/GSE TiO2/APTE/CPE Sol-gel nanofilm/IIP

Pb(II)

SWASV

0–100 μg L− 1

2.1 ng L− 1

[29]

Cu(II) Hg(II) Cd(II) and Pb(II) As(III) Cd(II) Cd(II) and Cu(II)

DPSV SWASV DPV LSV DPASV DPASV

0.2–2.0 μM – 5–150 μg L− 1 10–80 mg L− 1 2.9 nM–4.6 μM –

[30] [31] [32] [33] [34] [35]

MWCNT/SbNPs

Cd(II) and Pb(II)

CV

10.0–60.0 μg L− 1

AuNPs/rGO AuNPs/graphene

As(III) Hg(II)

CV SWASV

13.35–266.95 nM 0.12–29.9 pM

0.9 nM 0.017 μM – 10 mg L− 1 2.0 nM Cd: 0.050 Cu: 0.034 ng mL− 1 Cd: 0.77 μg L− 1 Pb: 0.65 μg L− 1 1.74 nM 0.03 pM

Nitrite

Amperometry

5–500 ppb

2.3 ppb

[39]

Nitrite Nitrite Hydrazine H2S

DPV SWV Amperometry CV

0.1–200 ppb 10.8–108 ppb 10–300 μM 1.25–112.5 μM

0.01 ppb 2.6 ppb 0.06 μM 0.3 μM

[40] [41] [42] [43]

[36] [37] [38]

Inorganic pollutants Nano-Au/poly(3methylthiophene)/ GCE Au-graphene-polyaniline/GCE Au/p-aminothiophenol-aunano PdNPs-PANI nanocomposites CNTs

Continued

Table 8.1  Application of various nanomaterials in the measurement of environmental pollutants—cont'd Nanomaterial

Pollutant

Method

Linear range

Detection limit

Ref.

AuNPs/MoS2/graphene PtNPs/PANI/graphene CuS-MWCNT CuNP-SWCNT-PPy

Nitrite Nitrite Nitrite NOx

Amperometry CV Amperometry CV

5.0 μM–5.0 mM 0.4 μM–7.01 mM 1.0 μM–8.1 mM 0.7–2000 μM

1.0 μM 0.13 μM 0.33 μM 0.7 μM

[44] [45] [46] [47]

Carbamate Dichlorophen Organophosphorus Cyhexatin Methyl parathion Monocrotophos and chlorpyrifos Parathion Methyl parathion Malathion

DPV SWAdSV SWSV DPV DPV DPV

0.34 nM 1.4 × 10–8 M 1.6 ng mL− 1 0.20 ng mL− 1 5.72 nM 0.051 pg·mL − 1

[44] [48] [49] [50] [51] [52]

SWASV DPV Amperometry

– 5.0 × 10− 8–2.9 × 10− 6 M 0.02–20 μg m− 1 1–500 ng mL− 1 0.5–65 μM 10− 10–10− 6 5 × 10− 8–10− 4 mg mL− 1 0.01–11.2 μM 0–2000 ppb 0.1 pM–100 nM

0.008 μM 1.21 ppb 0.037 pM

[53] [54] [55]

Dodecyl sulfate Dodecylbenzenesulfonate Sodium dodecyl sulfate Lauryl sulfate Dodecylbenzenesulfonate 2-(4-Methylphenoxy) ethanol Phosphate Cetylpyridinium bromide CPC CTAB Hyamine

Potentiometery

2.5 × 10− 7–4.5 × 10− 3 M

[56]

EMF EIS

10− 6–10− 1 M 2.0 × 10− 7–1.1 × 10− 3 3.6 × 10− 7–6.6 × 10− 4 M –

1.5 × 10− 7 2.5 × 10− 7 M 10− 6 M 1.2 × 10− 7 2.6 × 10− 7 M –

20–80 μM 5 × 10− 7–10− 4 M 1.5 × 10− 7–9.1 × 10− 4 3.5 × 10− 7–1.2 × 10− 3 2.0 × 10− 6–2.2 × 10− 3 M

6 μM 0.2 μM 1.2 × 10− 7 2.5 × 10− 7 1.5 × 10− 6 M

Pesticides Ag-doped ZnO nanorods/GO β-CDs/MWCNTs Graphene-nafion MIP/AuNPs/rGO MnO2/polythiophene/rGO CNTs-NH2/AgNPs-N-F-MoS2 Au-PdNPs/rGO CuO-TiO2 Pd/Au nanowires Detergents Graphene ZnO MWCNTs CNTs AuNPs/carbon black AuNPs MWCNTs

CV Amperometry CV Potentiometry

[57] [58] [59] [60] [61] [62]

CV, cyclic voltammetry; DPASV, differential pulse anodic stripping voltammetry; DPV, differential pulse voltammetry; EIS, electrochemical impedance spectroscopy; LSV, linear sweep voltammetry.

Functionalized nanomaterial-based for environmental sensors

149

8.2 Noble metal nanomaterials The chemical, physical, and electrochemical characteristics of noble metallic nanomaterials (e.g., Au, Ag, Pt, and Pd) depend on their shape and size. These features have been highlighted between researchers for use in various fields, including environmental applications. In addition to facilitating the synthesis of these nanoparticles, it is possible to functionalize them, and they can readily catalyze many reactions. Nanoparticles of these metals can play various roles in electrochemical sensors, including the catalytic role and electron transfer improvement [63]. In the following, the role of Nobel metal nanoparticles in electrochemical sensors in the environment will be reviewed according to the type of metal.

8.2.1 Gold nanomaterials Turkevich first synthesized gold nanoparticles (AuNPs) in 1951; Frens could synthesize AuNPs in controlled dimensions with stabilizer agents [64]. Like other nanoparticles, the top-down and down-up methods are used for the AuNPs synthesis. In the down-up method, the nanostructures’ size and shape were determined by choosing the type of Au salt, reducing agent, and other conditions of the synthesis determine. In the top-down method, nanoparticles can be synthesized by lithography. Mono-metallic, bi-metallic, and tri-metallic AuNPs are also used in electrochemical sensors [64]. The high surface-to-volume ratio of AuNPs, the adjustability of properties, for example, the optoelectronic properties of AuNPs by adjusting their size, and the ability to modify their surface are reasons why the use of AuNPs in different fields such as catalysis, imaging and biomedical and biological fields, data storage, electronics, photonics, drug delivery, and optical and electrochemical sensors has expanded [65]. Because AuNPs are stable and can be completely recovered from the reaction medium, they can be suitable electrochemical catalysts. The use of electrodes modified with AuNPs and the improvement of analytical method sensitivity also increase the penetration of electroactive species and the signal-to-noise ratio. The procedure is that the surface of the electrode is modified with AuNPs. Thus, the surface absorption of the analyte increases or catalyzing its redox reaction occurs [65]. In some cases, AuNPs are modified with molecules such as ligands, antibodies, aptamers, etc., to increase the adsorption of a particular molecule specifically. Aptamer term referred to single-stranded DNA/RNA or peptide molecules that bind to a specific target molecule [66,67]. There are many types of Au nanomaterials such as nanospheres, nanowires, nanorods, nanodisk, nanorings, nanocube, etc. [64]. The different types of gold nanostructures in Fig. 8.3 are shown schematically. Inorganic compounds (heavy metals, arsenic, and some anions such as nitrate, nitrite), organic compounds (aromatics, organophosphates, pesticides, and insecticides), and toxins are pollutants measured by electrochemical sensors based on AuNPs [68]. Jin et al. have used the photo-assisted method, deposited AuNPs with a diameter of 10 nm on TiO2 nanotubes with a diameter of 120 nm and a wall thickness of 60 nm, and a height of about 3 mm [69]. They used the amperometric sensor to measure chromium

150

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 8.3  Different types of gold nanostructures.

(VI). This method’s linear range was reported to be 0.1–105 μM, and the detection limit was reported as 0.03 μM. This sensor has been used to measure Cr(VI) in tap and lake water [69]. Al-Hossainy et  al. used AuNPs-graphene-selenocysteine-modified bismuth to measure cadmium and lead by square-wave anodic stripping in different and more recent work voltammetry (SWASV). In this work, the sensor’s detection limits were reported as 0.08 and 0.05 ppb for Cd and Pb ions, respectively. The linear ranges of both of them were 0.5–50 ppb [70]. Zhang et  al. measured mercury ions using an AuNPs-based electrochemical sensing [71]. In this work, first, the modification of the glassy carbon electrode (GCE) surface was performed with graphene, and then AuNPs were placed on graphene using the electrodeposition method. Next, Thymine-rich DNA strands were attached to AuNPs. Mercury, which has a strong tendency to bind to Thymine, was selectively attached to the modified electrode using Thymine-Hg2 +-Thymine interactions. Multistage modification of the electrode has enhanced the sensitivity and selectivity of the technique. So that this sensor’s detection limit was reported to be 0.001 aM with a linear range from 1.0 aM to 100 nM [71], some reports have suggested thymine-mercury-thymine interactions to produce the mercury-selective sensor. For example, Wang et al. selected GCE as a substrate for electrochemical reduction of Graphene oxide [72]. Then electrodeposition was applied using cyclic voltammetry to attach cysteamine-capped AuNPs on the modified electrode. Next, thymine-1-acetic acid is connected to the cysteamine to enhance the selectivity of the method. The linear range of the sensor was reported as 10 ng L− 1– 1.0 μg L− 1. 1.5 ng L− 1 [72].

Functionalized nanomaterial-based for environmental sensors

151

Nitrite is commonly used in various chemical and pharmaceutical productions. It is especially used for food preservation as well as in biochemical fields. The presence of nitrite in water and food raises the danger of various diseases such as stomach cancer and lowers blood oxygen levels. The usual methods of measuring nitrite and nitrate are complex and require advanced equipment. The use of AuNPs has created new methods in the area of electrochemistry and colorimetry. Numerous electrochemical sensors based on nanoparticles have been reported to measure nitrate and nitrite [73–76]. In general, AuNPs are deposited on the electrode and catalyze the oxidation reaction of nitrite. The concentration of nitrite is measured by one of the electrochemical methods, such as CV. Recently Liu et al. developed an electrochemical nitrite and bromate sensor based on AuNPs. In this case, Nafion and hemoglobin (Hb) were immobilized on a modified carbon ionic liquid electrode (CILE) with Zinc organic framework and AuNPs. Simultaneous use of these modifiers has made this sensor have unique features such as high surface to volume ratio, high thermal stability, fast electron transfer, and high conductivity. Stabilized Hb played a catalytic role in the reduction of nitrite and bromate in this sensor. This sensor’s linear ranges for bromate and nitrite were 0.5–10.0 mmol L− 1 and from 0.1 to 0.8 mmol L− 1, respectively, with limits detection of 0.83 mmol L− 1 and 0.03 mmol L− 1, respectively [77]. Another inorganic pollutant is hypochlorite. A variety of papers have been published on the use of electrochemical sensors based on AuNPs to measure it. For example, Tsai, et al. organized an electrochemical sensor using poly(3,4-ethylene dioxythiophene) and AuNPs to determine the linear range of 1.0 × 10− 6–9.32 × 10− 4 M. In this work, reduction of hypochlorite was catalyzed [78]. Arsenic is another inorganic pollutant, Which is also very toxic in small amounts [67]. Electrochemical sensors can often detect via anodic stripping voltammetry (ASV) [79,80]. In these methods, AuNPs are usually electrodeposited on the electrode, and then the arsenic is measured by ASV.

8.2.2 Silver nanoparticles Silver nanoparticles (AgNPs) have received a lot of attention due to their catalytic properties for many reactions, high electrical and thermal conductivity, antibacterial effects, and capacity to support surface-enhanced optical phenomena [81]. Combining these nanoparticles with materials like polymers, carbon and graphene materials, other metal nanoparticles and metal oxides, nanosilica, and a variety of fibers creates sensors with attractive properties and are used to measure various analytes, including environmental pollutants [82]. Jiang et al. developed an electrochemical sensor for measuring pesticides using AgNPs stabilized on nitrogen-coated graphene. The selectivity of this sensor has been significantly improved by attaching the aptamer to AgNPs. In addition to this sensor’s good selectivity, its wide linear range (1 × 10− 13–5 × 10− 9 M) and low detection limit (3.3 × 10− 14 M) are some of the unique features in acetamiprid measuring. This sensor does not require complex labeling and has good sensitivity [83]. In another study, de Lima et al. modified a GCE with AgNPs coated with chitosan and used it to measure pesticides containing nitro groups such as pendimethalin and ethyl parathion using SWASV method with linear ranges of 70–2000 nM and 40–8000 nM, respectively [84]. In addition to measuring pesticides, many electrochemical sensors

152

Functionalized Nanomaterial-Based Electrochemical Sensors

based on AgNPs have been reported to measure inorganic pollutants, including heavy metals and anions. For example, Tang et al. designed an aptasensor based on AgNPs to measure Pb2 + using Square wave voltammetry (SWV) [85]. Xing et al. developed an electrochemical sensor based on AgNPs-modified Nafion GCE for Cr(VI) measurement [86]. In another study, AgNPs were deposited on an electrode modified with silica spheres, and the resulting sensor was used to measure nitrobenzene derivatives and nitrite [87]. Guadagnini et al. modified the carbon dioxide electrode with AgNPs by potentiostatic reduction and used it to measure nitrite, nitrate, and iodate [88].

8.2.3 Platinum nanoparticles The electronic and electrocatalytic properties of platinum nanoparticles (PtNPs) besides low background current and high inertness, are the reason for the popularity of these nanoparticles in the field of electrochemical sensors [1]. The properties of PtNPs change with the interatomic distance, which in turn depends on the structure. Many parameters affect the electron transfer process, including crystal structure, chemical composition, and nanoparticle surface. PtNPs can be deposited on the surface of the electrode by electrochemical or photochemical methods or modified by reduction and metal-vapor synthesis. Liu et al. used an amperometric sensor based on PtNPs. The sensor was made by modifying the GCE with graphene and modified PtNPs with tyrosinase. It was used to measure pesticides such as chlorpyrifos, profenofos, and malathion with detection limits 0.2, 0.8, and 3 ppb, respectively. This enzyme catalyzes the conversion of the catechol to o-quinone. In the presence of pesticides, the enzyme was inhibited, and the signal is reduced. PtNPs and graphene substrates had a significant effect in increasing the sensitivity of the method [89]. Another study used molecular imprinting technology to produce an electrochemical sensor to measure atrazine [90]. In molecular imprinting, a polymer is synthesized in the presence of an analyte (as a template). Then, by removing the analyte, a polymer is obtained with cavities similar to the template’s shape and size. Therefore, there are different approaches that the polymer can interact to, specifically with the template in a complex matrix (depending on the type of template and monomer) [4,91,92]. To produce the atrazine (a kind of herbicide) sensor, C3N4 nanotubes were first modified with PtNPs and stabilized on the GCE surface. Phenol acted as a monomer for MIP synthesis, which has been synthesized electrochemically in the presence of atrazine. This method’s linear range was 1.0 × 10− 12–1.0 × 10− 10 M with a detection limit as 1.5 × 10− 13 M [90].

8.2.4 Palladium nanoparticles Palladium is another noble metal that plays an excellent catalytic role for many analytes, including toxins and environmental pollutants. The abundant presence of this metal than other noble metals has made its price lower and the modified sensors more affordable. The combination of palladium nanoparticles (PdNPs) with other metals and metal oxides, as well as with carbon materials such as graphene, has led to the development of a variety of sensors used to measure environmental pollutants. PdNPs

Functionalized nanomaterial-based for environmental sensors

153

improve the transfer of analyte mass by electron tunneling process [93,94]. Hydrazine is a pollutant that enters the environment and drinking water from the chemical industry and increases cancer risk if inhaled. So far, various electrochemical sensors have been reported to measure hydrazine based on PdNPs in combination with various materials such as carbon nanotube [95], ethylenediamine cellulose [96], and polyaniline [42], and onion-like mesoporous carbon vesicle [97]. Other pollutants, such as pesticides, have also been measured by electrochemical sensors based on PdNPs. Huang et al. prepared a methyl parathion sensor using a Pd/MWCNTs-modified electrode. The linear response was obtained in the range from 0.10 to 14 μg mL− 1, and 0.05 μg mL− 1 is a detection limit [98]. Mutharani et al. measured paraoxon-ethyl using a poly(N-isopropyl acrylamide)-chitosan microgel decorated with palladium nanoparticle in the range from 0.01 μM to 1.3 mM and a detection limit a 0.7 nM [99].

8.3 Metal oxide nanomaterials Nanostructures of metal oxides (MOs) are used in various fields such as gas sensors, lithium batteries, supercapacitors, catalysts, adsorbent, and energy-storage devices owing to their attractive electrical and optical characteristics, as well as the ability to be modified surface and high surface to volume ratio [100]. The use of these nanostructures in gas sensors is often based on the change of conduction and monitors environmental pollutants. These nanoparticles have also been used to measure water-soluble pollutants, such as anions and heavy metals [101]. The analytical performance of electrochemical sensors modified with nanostructures of MOs can be well-tuned by modulating size, morphology, the surface area of particles, and surface functionality. MOs nanomaterials with different morphologies have been synthesized through versatile approaches. Nanostructure MOs with energetic building blocks provide performance from electrical conduction to insulation and greatly catalysis to inert and the conductive sensing interface’s toughening. Several methods, including chemical covalent bonding, physical adsorption, electropolymerization, and electrodeposition, can be employed to achieve the strong affinity of metal oxide nanomaterials to the surface of the working electrode [102]. Metal oxide nanomaterials can be divided into MOs nanoparticles (NPs) and metal oxides nanocomposites. In both groups, major transition metals used in MOs include zirconium, iron, cobalt, copper, nickel, silver, manganese, vanadium, zinc, tungsten, and titanium [1]. MO NPs possess some disadvantages, including wide bandgap converting these materials like semiconductors or even insulators, weak kinetics of ion transport and delamination, and pulverization of electrode film arising from the expansion and contraction in the processes of charging/discharging. For overcoming these difficulties, the hybridization method with carbon-based materials, polymers, and other metal nanoparticles can be useful [103]. Fortunately, significant growth has occurred in the development of efficient electrochemical sensors based on metal oxide nanostructure to detect environmental contaminants, and the number of papers assigned to this issue has increased quickly in the past years.

154

Functionalized Nanomaterial-Based Electrochemical Sensors

Numerous chemical and physical routes are studied for the synthesis of MOs NPs. These techniques include precipitation, solvothermal, hydrothermal, sol-gel, electrochemical methods, laser ablation, and chemical and physical vapor deposition. Metal oxides nanostructures can be fabricated in various morphologies such as nanoparticles, nanocubes, nanotubes, nanoflowers, nanorods, nanowires, tapes, nanobelts [104]. Metal oxides such as zirconium, titanium, and aluminum are used to modify sensitive electrodes to organic pollutants such as electroactive nitroaromatic compounds such as methyl parathyroid, etc., because of the inherent tendency of these MOs to organic pollutants and high absorption properties due to their high adsorption sites [101]. For example, Liu and Lin deposited ZrO2 by electrochemical method on a gold electrode and made a sensitive organophosphate pesticide sensor [105]. Because ZrO2 tends to adsorb phosphorus groups, these pesticides were well adsorbed on the electrode and measured by stripping voltammetry method. The sensor’s detection limit for measuring methyl parathion was 3 ng mL− 1, and the linear range was 5–100 ng mL− 1. In another similar study, Wang and Li used a ZrO2/Au film electrode to measure parathion and reported a detection limit of 3 ng mL− 1 for this sensor [106]. TiO2 nanomaterials have been paid more attention since 1972, when the photocatalytic splitting of water was discovered by Fujishima and Honda using a TiO2 electrode under UV light [107]. TiO2 has been utilized in numerous promising fields ranging from photocatalysis to sensors owing to their interesting features such as biocompatible, nontoxic, cost-effective, optical, and electrical properties. Largescale preparation of TiO2 nanostructures can be obtained under mild conditions and temperatures, which promotes low-cost fabrication. TiO2 nanomaterials have been synthesized by various methods mentioned previously. The phase structures of the TiO2 materials in nature are three kinds, including rutile (tetragonal), anatase (tetragonal), and brookite (orthorhombic). The more applied structures are anatase and rutile because they are more stable than brookite [108]. The geometry of TiO2 materials could be altered from 0D (nanosphere) to 1D, or even 3D nanostructures. TiO2 nanostructures are more desirable for sensing usages due to their better electron transition and larger surface area. In most studies, TiO2 modified with other components like noble metals, polymer, and biomolecule have been applied in electrochemical sensing. Electrode fabricated with pure TiO2 nanomaterials cannot comply with the sensing requirements such as sensitivity, response time, detection range, and operating temperature [109]. TiO2-based sensors can be used for detecting various air pollutant gases (SO2, CO, etc.). Kim et al. reported a CO gas sensor based on an MWCNTs-modified TiO2 thin film [110]. Incorporation of MWCNTs and TiO2 enhanced sensitivity, electrical conductivity, and surface area. Zhang et al. determined arsenic(III) using an electrochemical sensor based on TiO2-nanoparticles-modified gold strip electrode. A chemical modification method was used to construct the thinfilm electrochemical sensing based on the gold strip electrode covering with TiO2. At optimal conditions, As(III) peak current linearly increased with concentrations in the range of 10–80 mg L− 1 [33]. Metal oxide nanoparticles, such as Fe3O4, can also be used in polymer-based electrochemical sensors. Especially iron oxide nanoparticles, which have received a lot of

Functionalized nanomaterial-based for environmental sensors

155

attention due to their magnetic properties. Tang et al. used the Fe3O4@Au sphere to develop a molecularly imprinted polymer (MIP) to measure parathion-methyl. This type of polymer will be described in Section 8.4 (polymer nanomaterials) [111]. Hung et al. prepared a 4-nonylphenol electrochemical sensor based on MIP using titanium oxide and AuNPs [112]. Another role of these nanoparticles in enzymatic electrochemical sensors can be a platform for enzyme binding. Chauhan et al. used acetylcholinesterase bonded covalently to Fe3O4 nanoparticles deposited on MWCNTs-ITO to measure pesticides. The linear ranges for malathion (0.1–70 nM), chlorpyrifos (0.1–50 nM), monocrotophos (0.1–70 nM), and endosulfan (0.1–100 nM) were obtained. Pesticide play the role of enzyme inhibitors. Recently, ZnO nanomaterials have been noticed as “future promising material” by the scientific community. ZnO with broad band-gap shows unique electrical, optical, and structural properties. These features are why ZnO is considered appropriate material for numerous applications, including solar cells, biological labeling, drug delivery, photocatalytic and photoluminescence fields, and sensors [113,114]. Also, ZnO materials with excellent electrochemical activity and high stability under thermal and chemical fluctuations have been considered an excellent choice for electrochemical sensors that control sensitivity, stability, and selectivity. ZnO has been fabricated in diverse nano shapes, including nanorods, nanowires, and nanocubes [115]. The electrode surface can be modified with these nanomaterials for the manufacturing sensor to detect harmful pollutants effectively. A gold electrode modified ZnO nanoparticles was applied to analyze Cd (II) through the cyclic voltammetry and chronoamperometric methods [116]. Using chronoamperometry, a linear range was obtained from 5 to 50 ppb. The detection limit was 4 ppb. Other metal oxides can also catalyze the redox reaction. For example, CdO nanoparticles are electrocatalytic oxidants of redox trichloroacetic acid, a pollutant in the haloacetic acid family that increases the risk of cancer and pregnancy problems [117]. The detection limit of this sensor was 2.3 × 10− 6 M.

8.4 Carbon nanomaterials In the past decades, carbon nanomaterials (CNMs) have received particular attention owing to their remarkable structural and physical properties. These properties include good conductivity, low cost, high stability, and facile surface functionalization that offer various advantages, such as chemical stability, high electrical conductivity, biocompatibility, high surface-to-volume ratio, and robust mechanical strength [118]. CNMs can be designed in all reduced dimensionalities, including 0D (carbon dots), 1D (carbon nanotubes (CNTs)), 2D (graphene sheets), and 3D (fullerite, nanocrystalline diamond films). sp2-bonded graphitic carbon is found in all structures [119]. Advancement in producing types of carbon-based nanostructures and surface modification of nanomaterials has increased interest in applying CNMs in various areas, such as optoelectronics, electronic, and photovoltaic, ­catalytic, and sensing applications. Fig. 8.4 shows

156

Functionalized Nanomaterial-Based Electrochemical Sensors

Fig. 8.4  Various types of CNMs.

the different types of CNMs. This section ­discusses different electrochemical sensors based on CNMs for the detection of environmental pollutants.

8.4.1 Carbon dots Carbon dots (CDs) appear as a new group of CNMs possessing a quasispherical structure with a size below 10 nm. They were first found out when single-walled CNTs were purified via preparative electrophoresis in 2004. CDs are potentially considered superior in intriguing physicochemical characteristics, including low cytotoxicity, biocompatibility, high aqueous solubility, facile modification, and large surface-to-­ volume ratio. Their features give them a high potential in optical, sensing, and catalytic and biological applications. Diverse procedures for the synthesis of CDs have been classified as top-down or bottom-up [66,120,121]. CDs/ZrO2 nanocomposite was deposited by the electrochemical method on GCE and used to detect methyl parathion. Organophosphorus pesticide was well adsorbed on the electrode and was measured by adsorptive stripping voltammetry. The better performance was obtained from a combination of the advantages of the quick ­electron-transmission and a high surface area of CDs with the robust tend of ZrO2 to the phosphate group. A linear response was obtained by changing concentrations from 0.2 to 48 ng mL− 1, and a detection limit was 0.056 ng mL− 1 [122]. Shao et al. highlighted a sensor based on the electrochemical technique for detecting Cu+ 2 based on the high affinity between TPEA and Cu+ 2. CDs-TPEA hybridized nanocomposites were assembled on the electrode, and Cu+ 2 was measured by differential pulse anodic stripping voltammetry (DPASV). A linear range from 1 to 60 μM with a detection limit 100 nM was achieved [123].

Functionalized nanomaterial-based for environmental sensors

157

8.4.2 Carbon nanotubes Carbon nanotubes (CNTs) refers to tubular nanostructures with a hexagonal lattice of sp2 carbons that have received attention from their discovery in 1991 [124]. CNTs can be considered into two critical groups based on the number of graphene layers in the walls of the tubular structure; (i) single-walled carbon nanotubes (SWNTs) and (ii) multiwalled carbon nanotubes (MWCNTs). Several synthesis techniques have been developed for the preparation CNTs, including laser vaporization, chemical vapor deposition (CVD), and electrical arc discharge [119]. CVD was chosen as a commercial approach, owing to simplicity, versatility, economical technique, and capability in easily modification and scaled-up in terms of quantities manufactured. Interesting properties, including electrical conductivity, large surface area, high tensile strength, fast charge transfers, and excellent electrocatalytic ability, give CNTs a high potential in environmental electrochemical sensors [125]. Wu and his group developed an electrochemical sensor based on Fe3O4 and fluorinated MWCNTs for the simultaneous determination of heavy metal ions (Cu+ 2, Cd+ 2, Pb+ 2, and Hg+ 2). The strong negative charge of semiionic CF bonds can enhance the adsorption of heavy metal cations measured by SWASV. Linear detection ranges (μM) and limit of detections (nM) were achieved for Cd+ 2 (0.5–30.0 and 0.05), Pb+ 2 (0.5–30.0 and 0.08), Cu+ 2 (0.5–30.0 and 0.02), and Hg+ 2 (0.5–20.0 and 0.05), respectively [126]. A modified carbon paste electrode with CNTs was applied for voltammetric detection of diazinon as a common pesticide. The sensor response was increased by using CNTs due to high surface area, improving the electrocatalytic activity and the electron transfer. A sensor displayed a linear range from 1×10− 10 to 6×10− 8 M with 4.5×10− 10 as a detection limit [127]. Asad et al. presented an H2S gas sensor working at room temperature based on Cu NPs-SWCNTs. The sensor illustrated a linear response over a range of 5–150 ppm with a recovery time of 10–15 s. The fabricated sensors can be done a real-time analysis of H2S with high sensitivity and selectivity [128]. Chen’s group reported preparing an amperometric sensor of nitrite that ­carboxylated-SWCNT with TiN NPs is the sensing element. The detection limit was obtained as low as 4 nM, and the analytical range was 6 nM–950 μM. The authors outlined fast response time (4 s), and long-term stability was also achieved by the fabricated sensor [129].

8.4.3 Graphene Graphene term is referred to as a combination of word graphite and the suffix-ene. Graphene is referenced to single two-dimensional sheets of sp2 hybridized carbons packed in hexagonal or honeycomb-like networks. Each carbon atom of the graphene structure is energetic, covalently bonded to adjacent carbon that its thickness is equal to the diameter of an atom [130]. Various processes for preparing graphene have been developed, such as electrochemical reduction, CVD, the intercalative expansion of graphite, and exfoliation. Graphene exhibits many interesting physicochemical and electrical properties that make it an ideal candidate for the fabrication of an electrochemical sensor. Recently, more attention has been devoted to derivatives of graphene,

158

Functionalized Nanomaterial-Based Electrochemical Sensors

especially graphene oxide (GO), three-dimensional (3D) graphene, and reduced graphene oxide (rGO) owing to the existence of the free π-π electron, aromatic ring, and reactive functional groups [119,131]. Li et  al. have developed devices based on graphene for NO gas determination prepared by alternating current dielectrophoresis (ac-DEP). The sensor is composed of the sensitive Pd-decorated rGO channels and CVD-grown graphene electrodes. Consequently, at a response time of 700 s, sensitive NO detection has been obtained, ranging from 2 to 420 ppb at room temperature. The combination of Pd- and CVDgrown graphene contacts of RGO improve the sensitivity and stability of NO sensors [132]. Manna and Raj employed S-doped porous rGO prepared via thermal annealing for effective elimination and electrochemical determination of Hg+ 2. The linear range of Hg was obtained from 0 to 600 nM by the SWASV method. Both porosity and presence of a large amount of S offered a detection limit as low as 0.5 nM [133]. In another study, Noyrod et al. fabricated a graphene-based electrochemical sensor by a ­single-drop analysis to determine isoproturon and carbendazim simultaneously. Linear ranges and detection limits were achieved 0.02–10.0 and 0.02 mg L− 1 for isoproturon and 0.50–10.0 and 0.11 mg L− 1 for carbendazim, respectively [134]. Zhang and coworkers outlined the development of an electrochemical sensor relying on reduced holey graphene (RHG) with in-plane nanopores for detecting the nitrate ions. The high amounts of edge planes and the defect density of RHG can accelerate the electron and mass transport that improve the sensor’s performance. The linear relationship between nitrite concentrations and peak response was observed in the range of 0.2 μM–10 mM with 0.054 μM as a limit of detection [135].

8.5 Polymer nanomaterials Polymeric nanomaterials are colloid with a size range 10 nm–1 μm and solid in nature. Polymer-based nanomaterials can be found in two groups, (i) natural polymers such as chitosan, starch, alginate, cellulose with different functional groups that obtained by physical and chemical techniques and (ii) synthesized polymer materials such as polylactic (PLA), polyurethane (PU), poly (methyl methacrylate), polyester, poly-β-hydroxybutyrate (PHB), polyvinylpyrrolidone (PVP) and polyamino acid produced through chemical methods and enzyme hydrolysis [136]. Depending on the preparation process, two types of structures can be devoted to polymeric nanoparticles, nanosphere, and nanocapsule [137]. Recently, polymer nanomaterials are wildly studied due to unique and intriguing properties, including large surface area, high electrical conductivity, and rapid electron transfer that make them appealing for manufacturing chemical and biological sensors. Unlike pure conducting polymers with few problems such as low selectivity and sensitivity, poisoning of surface, sensing platforms based on the polymeric nanomaterials have shown fascinating features of linearity, sensitivity, selectivity, and easy manufacturability. Coupling polymers with nanomaterials that have well-known electrochemical significance are called polymer nanocomposites (PNCs), which leads to enhance electrochemical sensing properties due to increased surface area and ­electrical

Functionalized nanomaterial-based for environmental sensors

159

c­ onductivity. For such purposes, nanomaterials are being used most, including metal oxide nanoparticles, metal nanoparticles, CNTs, and graphene [138]. Chemical or electrochemical polymerization methods have been used for preparing of PNCs. Since the film thickness and other polymer coating specifications can be controlled by adjusting the electrochemical, the electrochemical technique is usually chosen [139]. Far from the economic aspect, unique properties of the polymer nanomaterials-based sensors provide advantages as well as biocompatibility, improved electronic attributes, a high-edge plane-basal plane ratio, controllable chemical/electrochemical properties, reversible doping/dedoping processes, active electrode kinetics, and environmental stability [138]. Today, there has been an explosion of interest in polymer nanomaterials and PNCs for the development of electrochemical sensors. The application of these nanomaterials in the fabrication of electrochemical sensors for determining environmental pollutants is mentioned in the table, and some applications are pronounced in the following. Navale et al. have designed the gas sensor-based polypyrrole (PPy)/a-Fe2O3 nanocomposites to detect several oxidizing and reducing gases (NO2, Cl2, and H2S, NH3) gases at room temperature. Compared to a PPy-based sensor, this gas sensor shows excellent gas-sensing advantages such as good stability, fast response, and shorter recovery times, which can be applied as selective NO2 gas sensing with high performance. Wei et al. prepared a graphene/polyaniline (GN/PANI) nanocomposite electrode by a reverse-phase suspension polymerization technique in the presence of PVP for the ultrasensitive detection of Pb(II). The GN/PANI nanocomposite with the large specific surface area, satisfactory repeatability, long-term stability, and simple synthesis leads to rising electrochemical conductivity and generating four times increase in peak current. The detection limit and the sensor’s linear range were found 0.06088 nM and 1.0 × 10− 9–1.0 × 10− 4 M, respectively [140]. Nirmal Prabhakar and her coworkers prepared a chitosan‑iron oxide (CHIT-IO) nanocomposite film on a fluorine tin oxide (FTO) electrode. They used this electrode in electrochemical aptasensor for the detection of malathion as an organophosphorus insecticide. The biotinylated aptamer of the malathion was immobilized onto the prepared electrode by using streptavidin as a linking molecule. The LOD of the sensor with CHIT-IO/FTO-based aptaelectrode was about 0.001 ng mL− 1 within 15 min. The high specificity and improved detection limit were obtained because of the coupling properties of chitosan, iron oxide, and FTO aptaelectrode [141]. Duan and Zheng designed an electrochemical enzyme-free sensor for nitrite (NO2−) based on the porous coralloid Polyaniline/tin dioxide (PANI/SnO2). Combining the p-type PANI as electron donor and n-type semiconductor SnO2 as an electron acceptor produces a p-n junction, enhancing the height of the depletion barrier to improve the response of the NO2−. Electrochemical investigations show that the PANI/SnO2 nanocomposites have an excellent electrochemical performance towards the oxidation of NO2− with a linear range from 0.12 μM to 7.8 mM and a detection limit of 0.04 μM [142]. The imprinting polymers, a group of polymeric nanomaterials, are considered an effective method for highly selective detection of various species through artificial recognition. The electrochemical-sensing-based MIPs can be employed for monitoring a wide range of pollutants, including pesticides and heavy metals.

160

Functionalized Nanomaterial-Based Electrochemical Sensors

A GCE of the electrochemical molecularly imprinted sensor was coated by reduced graphene oxide and AuNPs (rGO@Au) for carbofuran detection. The electrochemical signal and recognition capacity of the sensor have been improved by introducing rGO@Au into the imprinted film improve. Under the optimal conditions, the sensor displayed a good linear relationship over the range from 5.0 × 10− 8 to 2.0 × 10− 5 M, with a detection limit of 2.0 × 10− 8 M [143]. Different heavy metals can be detected simultaneously through multi-template imprinted nanowires on the surface of MWCNTs coated by a layer of polyarginine. Pb2 +, Cd2 +, Cu2 + ions as templates were selectively measured by a differential pulse stripping voltammetry [144].

8.6 Conclusions and perspectives The intriguing features of electrochemical sensors give them high potential in different applications, including environmental monitoring. The use of nanomaterials to modify electrodes in the role of catalyst or selective adsorbent has received much attention due to their variety in types and shapes. Due to the increasing and rapid advancement of science in various fields, including the synthesis of new nanometer materials, it is expected that various electrochemical sensors will be built and used to measure pollutants in the future.

References [1] G. Maduraiveeran, W. Jin, Trends Environ. Anal. Chem. 13 (2017) 10–23. [2] T. Rasheed, M. Bilal, F. Nabeel, M. Adeel, H.M.N. Iqbal, Environ. Int. 122 (2019) 52–66. [3] L. Rassaei, F. Marken, M. Sillanpää, M. Amiri, C.M. Cirtiu, M. Sillanpää, TrAC Trends Anal. Chem. 30 (2011) 1704–1715. [4] N. Kazemifard, A.A. Ensafi, B. Rezaei, Food Chem. 310 (2019) 125812. [5] Z. Saberi, B. Rezaei, A.A. Ensafi, Microchim. Acta 186 (2019) 273. [6] D.B. Alcântara, T.S.M. Fernandes, H.O. Nascimento, A.F. Lopes, M.G.G. Menezes, A.C.A. Lima, T.V. Carvalho, P. Grinberg, M.A.L. Milhome, A.H.B. Oliveira, Food Chem. (2019) 124958. [7] A.L. Srivastav, M. Ranjan, Inorganic Pollutants in Water, Elsevier, 2020, pp. 1–15. [8] D.B. Kim-Shapiro, A.N. Schechter, M.T. Gladwin, Arterioscler. Thromb. Vasc. Biol. 26 (2006) 697–705. [9] M. Richards, M. Ghanem, M. Osmond, Y. Guo, J. Hassard, Ecol. Model. 194 (2006) 274–286. [10] L.E. Mitchell, E.T. Crosman, A.A. Jacques, B. Fasoli, L. Leclair-Marzolf, J. Horel, D.R. Bowling, J.R. Ehleringer, J.C. Lin, Atmos. Environ. 187 (2018) 9–23. [11] A.R. Firooz, A.A. Ensafi, K.S. Hoseini, N. Kazemifard, Mater. Sci. Eng. C 38 (2014) 73–78. [12] A.R. Firooz, A.A. Ensafi, N. Kazemifard, R. Khalifeh, Sens. Actuators B 176 (2013) 598–604. [13] R.K. Sharma, M. Agrawal, J. Environ. Biol. 26 (2005) 301–313.

Functionalized nanomaterial-based for environmental sensors

161

[14] M. Jaishankar, T. Tseten, N. Anbalagan, B.B. Mathew, K.N. Beeregowda, Interdiscip. Toxicol. 7 (2014) 60–72. [15] G.A. Engwa, P.U. Ferdinand, F.N. Nwalo, M.N. Unachukwu, Poisoning in the Modern World-New Tricks for an Old Dog?, IntechOpen, 2019. [16] J.C.P. Penteado, O.A. El Seoud, L.R.F. Carvalho, Quim. Nova 29 (2006) 1038–1046. [17] S.A. Mousavi, F. Khodadoost, Environ. Sci. Pollut. Res. (2019) 1–10. [18] A.D. Chaturvedi, K.L. Tiwari, Recent Res. Sci. Technol. 5 (2013) 12–16. [19] A. Chen, S. Chatterjee, Chem. Soc. Rev. 42 (2013) 5425–5438. [20] N.R. Stradiotto, H. Yamanaka, M.V.B. Zanoni, J. Braz. Chem. Soc. 14 (2003) 159–173. [21] F. Brandl, N. Bertrand, E.M. Lima, R. Langer, Nat. Commun. 6 (2015) 1–10. [22] D.W. Kimmel, G. LeBlanc, M.E. Meschievitz, D.E. Cliffel, Anal. Chem. 84 (2012) 685–707. [23] A. Chen, P. Holt-Hindle, Chem. Rev. 110 (2010) 3767–3804. [24] C. Dhand, N. Dwivedi, X.J. Loh, A.N.J. Ying, N.K. Verma, R.W. Beuerman, R. Lakshminarayanan, S. Ramakrishna, RSC Adv. 5 (2015) 105003–105037. [25] I.-H. Cho, D.H. Kim, S. Park, Biomater. Res. 24 (2020) 1–12. [26] C.M. Welch, O. Nekrassova, R.G. Compton, Talanta 65 (2005) 74–80. [27] B.K. Jena, C.R. Raj, Talanta 76 (2008) 161–165. [28] L. Zhu, L. Xu, B. Huang, N. Jia, L. Tan, S. Yao, Electrochim. Acta 115 (2014) 471–477. [29] P. Kanyong, S. Rawlinson, J. Davis, Microchim. Acta 183 (2016) 2361–2368. [30] W. Xiong, L. Zhou, S. Liu, Chem. Eng. J. 284 (2016) 650–656. [31] W.-Y. Zhou, J.-Y. Liu, J.-Y. Song, J.-J. Li, J.-H. Liu, X.-J. Huang, Anal. Chem. 89 (2017) 3386–3394. [32] H. Dai, N. Wang, D. Wang, H. Ma, M. Lin, Chem. Eng. J. 299 (2016) 150–155. [33] X. Zhang, T. Zeng, C. Hu, S. Hu, Anal. Methods 8 (2016) 1162–1169. [34] S. Ramezani, M. Ghobadi, B.N. Bideh, Sens. Actuators B 192 (2014) 648–657. [35] B.B. Prasad, D. Jauhari, A. Verma, Talanta 120 (2014) 398–407. [36] A.M. Ashrafi, S. Cerovac, S. Mudrić, V. Guzsvány, L. Husáková, I. Urbanová, K. Vytřas, Sens. Actuators B 191 (2014) 320–325. [37] W.-W. Li, F.-Y. Kong, J.-Y. Wang, Z.-D. Chen, H.-L. Fang, W. Wang, Electrochim. Acta 157 (2015) 183–190. [38] J. Gong, T. Zhou, D. Song, L. Zhang, Sens. Actuators B 150 (2010) 491–497. [39] X. Huang, Y. Li, Y. Chen, L. Wang, Sens. Actuators B 134 (2008) 780–786. [40] X. Ma, T. Miao, W. Zhu, X. Gao, C. Wang, C. Zhao, H. Ma, RSC Adv. 4 (2014) 57842–57849. [41] A. Üzer, Ş. Sağlam, Z. Can, E. Erçağ, R. Apak, Int. J. Mol. Sci. 17 (2016) 1253. [42] S. Ivanov, U. Lange, V. Tsakova, V.M. Mirsky, Sens. Actuators B 150 (2010) 271–278. [43] N.S. Lawrence, R.P. Deo, J. Wang, Anal. Chim. Acta 517 (2004) 131–137. [44] Y. Han, R. Zhang, C. Dong, F. Cheng, Y. Guo, Biosens. Bioelectron. 142 (2019) 111529. [45] S. Zhang, B.-Q. Li, J.-B. Zheng, Anal. Methods 7 (2015) 8366–8372. [46] S. Zhang, B. Li, Q. Sheng, J. Zheng, J. Electroanal. Chem. 769 (2016) 118–123. [47] S. Prakash, S. Rajesh, S.K. Singh, K. Bhargava, G. Ilavazhagan, V. Vasu, C. Karunakaran, Talanta 85 (2011) 964–969. [48] K. Sipa, M. Brycht, A. Leniart, P. Urbaniak, A. Nosal-Wiercińska, B. Pałecz, S. Skrzypek, Talanta 176 (2018) 625–634. [49] R. Xue, T.-F. Kang, L.-P. Lu, S.-Y. Cheng, Anal. Lett. 46 (2013) 131–141. [50] C. Zhang, F. Zhao, Y. She, S. Hong, X. Cao, L. Zheng, S. Wang, T. Li, M. Wang, M. Jin, F. Jin, H. Shao, J. Wang, Sens. Actuators B 284 (1) (2019) 13–22. [51] T. Ramachandran, V.V. Dhayabaran, J. Mater. Sci. Mater. Electron. 30 (2019) 12315–12327.

162

Functionalized Nanomaterial-Based Electrochemical Sensors

[52] D. Song, Y. Wang, X. Lu, Y. Gao, Y. Li, F. Gao, Sens. Actuators B 267 (2018) 5–13. [53] M.N. Jahromi, F. Tayadon, H. Bagheri, Int. J. Environ. Anal. Chem. (2019) 1–17. [54] X. Tian, L. Liu, Y. Li, C. Yang, Z. Zhou, Y. Nie, Y. Wang, Sens. Actuators B 256 (2018) 135–142. [55] X. Lu, L. Tao, Y. Li, H. Huang, F. Gao, Sens. Actuators B 284 (2019) 103–109. [56] O. Galović, M. Samardžić, M. Hajduković, M. Sak-Bosnar, Sens. Actuators B 236 (2016) 257–267. [57] S.S. Sanjay, A.C. Pandey, P. Ankit, M.C. Chattopadhyaya, Proc. Natl. Acad. Sci., India, Sect. A 83 (2013) 279–285. [58] N. Sakač, M. Karnaš, M. Jozanović, M. Medvidović-Kosanović, S. Martinez, J. Macan, M. Sak-Bosnar, Anal. Methods 9 (2017) 2305–2314. [59] Y. Patiño, E. Díaz, M.J. Lobo-Castañón, S. Ordóñez, Water Sci. Technol. 77 (2018) 2436–2444. [60] D. Talarico, F. Arduini, S. Cinti, A. Amine, D. Moscone, G. Palleschi, Proc. 2015 18th AISEM Annu. Conf. AISEM 2015, 2015, pp. 3–6. [61] Y. Wang, J. Zhi, Y. Liu, J. Zhang, Electrochem. Commun. 13 (2011) 82–85. [62] M. Hajduković, M. Samardžić, O. Galović, A. Széchenyi, M. Sak-Bosnar, Sens. Actuators B 251 (2017) 795–803. [63] T.K. Sau, A.L. Rogach, F. Jäckel, T.A. Klar, J. Feldmann, Adv. Mater. 22 (2010) 1805–1825. [64] W. Jin, G. Maduraiveeran, Trends Environ. Anal. Chem. 14 (2017) 28–36. [65] C. Wang, C. Yu, Rev. Anal. Chem. 32 (2013) 1–14. [66] Z. Saberi, B. Rezaei, P. Rezaei, A.A. Ensafi, Spectrochim. Acta A Mol. Biomol. Spectrosc. (2020) 118197. [67] A.A. Ensafi, N. Kazemifard, B. Rezaei, Biosens. Bioelectron. 77 (2016) 499–504. [68] P.B. Tchounwou, C.G. Yedjou, A.K. Patlolla, D.J. Sutton, Molecular, Clinical and Environmental Toxicicology Volume 3: Environmental Toxicology, vol. 101, 2012. [69] W. Jin, G. Wu, A. Chen, Analyst 139 (2014) 235–241. [70] A.F. Al-Hossainy, A.A.I. Abd-Elmageed, A.T.A. Ibrahim, Arab. J. Chem. 12 (2019) 2853–2863. [71] Y. Zhang, G.M. Zeng, L. Tang, J. Chen, Y. Zhu, X.X. He, Y. He, Anal. Chem. 87 (2015) 989–996. [72] N. Wang, M. Lin, H. Dai, H. Ma, Biosens. Bioelectron. 79 (2016) 320–326. [73] O. Koyun, Y. Sahin, Ionics (Kiel) 24 (2018) 3187–3197. [74] S.S. Huang, L. Liu, L.P. Mei, J.Y. Zhou, F.Y. Guo, A.J. Wang, J.J. Feng, Microchim. Acta 183 (2016) 791–797. [75] S.J. Li, M.M. Lv, J.J. Meng, L.Z. Zhao, Ionics (Kiel) 24 (2018) 3177–3186. [76] D. Rao, Q. Sheng, J. Zheng, Anal. Methods 8 (2016) 4926–4933. [77] J. Liu, W. Weng, C. Yin, G. Luo, H. Xie, Y. Niu, X. Li, G. Li, Y. Xi, Y. Gong, S. Zhang, W. Sun, Int. J. Electrochem. Sci. 14 (2019) 1310–1317. [78] T.H. Tsai, S. Thiagarajan, S.-M. Chen, Int. J. Electrochem. Sci. 6 (2011) 3878–3889. [79] J.-F. Huang, H.-H. Chen, Talanta 116 (2013) 852–859. [80] M.M. Hossain, M.M. Islam, S. Ferdousi, T. Okajima, T. Ohsaka, Electroanalysis 20 (2008) 2435–2441. [81] A.A. Ensafi, N. Kazemifard, B. Rezaei, RSC Adv. 5 (2015) 40088–40093. [82] A.S. Rad, A. Mirabi, E. Binaian, H. Tayebi, Int. J. Electrochem. Sci. 6 (2011) 3671–3683. [83] D. Jiang, X. Du, Q. Liu, L. Zhou, L. Dai, J. Qian, K. Wang, Analyst 140 (2015) 6404–6411. [84] C.A. de Lima, E.R. Santana, J.V. Piovesan, A. Spinelli, Anal. Bioanal. Chem. 408 (2016) 2595–2606.

Functionalized nanomaterial-based for environmental sensors

163

[85] S. Tang, P. Tong, X. You, W. Lu, J. Chen, G. Li, L. Zhang, Electrochim. Acta 187 (2016) 286–292. [86] S. Xing, H. Xu, J. Chen, G. Shi, L. Jin, J. Electroanal. Chem. 652 (2011) 60–65. [87] P. Rameshkumar, R. Ramaraj, J. Electroanal. Chem. 731 (2014) 72–77. [88] L. Guadagnini, D. Tonelli, Sens. Actuators B 188 (2013) 806–814. [89] T. Liu, M. Xu, H. Yin, S. Ai, X. Qu, S. Zong, Microchim. Acta 175 (2011) 129–135. [90] M.L. Yola, N. Atar, Ind. Eng. Chem. Res. 56 (2017) 7631–7639. [91] A.A. Ensafi, N. Kazemifard, B. Rezaei, Sens. Actuators B 252 (2017) 846–853. [92] S. K. Haghani, A. A. Ensafi, N. Kazemifard and B. Rezaei, IEEE Sensors J. [93] C.C. Ndaya, N. Javahiraly, A. Brioude, Sensors 19 (2019) 4478. [94] B. Jaleh, S. Karami, M. Sajjadi, B.F. Mohazzab, S. Azizian, M. Nasrollahzadeh, R.S. Varma, Chemosphere 246 (2020) 125755. [95] J. Zhao, M. Zhu, M. Zheng, Y. Tang, Y. Chen, T. Lu, Electrochim. Acta 56 (2011) 4930–4936. [96] H. Ahmar, S. Keshipour, H. Hosseini, A.R. Fakhari, A. Shaabani, A. Bagheri, J. Electroanal. Chem. 690 (2013) 96–103. [97] X. Bo, J. Bai, J. Ju, L. Guo, Anal. Chim. Acta 675 (2010) 29–35. [98] B. Huang, W.-D. Zhang, C.-H. Chen, Y.-X. Yu, Microchim. Acta 171 (2010) 57–62. [99] B. Mutharani, P. Ranganathan, S.-M. Chen, C. Karuppiah, Microchim. Acta 186 (2019) 167. [100] M. Karimi-Shamsabadi, M. Behpour, A.K. Babaheidari, Z. Saberi, J. Photochem. Photobiol. A Chem. 346 (2017) 133–143. [101] X.-Y. Yu, Z.-G. Liu, X.-J. Huang, Trends Environ. Anal. Chem. 3 (2014) 28–35. [102] J.M. George, A. Antony, B. Mathew, Microchim. Acta 185 (2018) 358. [103] Y. Li, B. Tan, Y. Wu, Nano Lett. 8 (2008) 265–270. [104] J.M. Patete, X. Peng, C. Koenigsmann, Y. Xu, B. Karn, S.S. Wong, Green Chem. 13 (2011) 482–519. [105] G. Liu, Y. Lin, Anal. Chem. 77 (2005) 5894–5901. [106] M. Wang, Z. Li, Sens. Actuators B 133 (2008) 607–612. [107] A. Fujishima, K. Honda, Nature 238 (1972) 37–38. [108] J. Bai, B. Zhou, Chem. Rev. 114 (2014) 10131–10176. [109] O.K. Varghese, G.K. Mor, M. Paulose, C.A. Grimes, Nano Lett. 9 (2009) 731–737. [110] H. Kim, M.-H. Hong, H.W. Jang, S.-J. Yoon, H.-H. Park, Thin Solid Films 529 (2013) 89–93. [111] X. Tang, D. Zhang, T. Zhou, D. Nie, Q. Yang, L. Jin, G. Shi, Anal. Methods 3 (2011) 2313–2321. [112] J. Huang, X. Zhang, S. Liu, Q. Lin, X. He, X. Xing, W. Lian, D. Tang, Sens. Actuators B 152 (2011) 292–298. [113] D. Khayyami, A.A. Ensafi, N. Kazemifard, B. Rezaei, Environ. Sci. Pollut. Res. (2020) 1–13. [114] S.K. Mehta, K. Singh, A. Umar, G.R. Chaudhary, S. Singh, Electrochim. Acta 69 (2012) 128–133. [115] Y. Ka, H.-R. Jang, W.-S. Choi, Sci. Adv. Mater. 8 (2016) 382–387. [116] G. Bhanjana, N. Dilbaghi, N.K. Singhal, K.-H. Kim, S. Kumar, J. Ind. Eng. Chem. 53 (2017) 192–200. [117] M. Najafi, S. Darabi, A. Tadjarodi, M. Imani, Electroanalysis 25 (2013) 487–492. [118] B.-R. Adhikari, M. Govindhan, A. Chen, Sensors 15 (2015) 22490–22508. [119] V. Georgakilas, J.A. Perman, J. Tucek, R. Zboril, Chem. Rev. 115 (2015) 4744–4822. [120] A.A. Ensafi, S. Hghighat Sefat, N. Kazemifard, B. Rezaei, F. Moradi, Sens. Actuators B 253 (2017) 451–460.

164

Functionalized Nanomaterial-Based Electrochemical Sensors

[121] A.A. Ensafi, S.H. Sefat, N. Kazemifard, B. Rezaei, J. Iran. Chem. Soc. 16 (2019) 355–363. [122] P. Reddy Prasad, E.B. Naidoo, N.Y. Sreedhar, Arab. J. Chem. 12 (2019) 2300–2309. [123] X. Shao, H. Gu, Z. Wang, X. Chai, Y. Tian, G. Shi, Anal. Chem. 85 (2013) 418–425. [124] Y. Yan, J. Miao, Z. Yang, F.-X. Xiao, H. Bin Yang, B. Liu, Y. Yang, Chem. Soc. Rev. 44 (2015) 3295–3346. [125] I.V. Zaporotskova, N.P. Boroznina, Y.N. Parkhomenko, L.V. Kozhitov, Mod. Electron. Mater. 2 (2016) 95–105. [126] W. Wu, M. Jia, Z. Zhang, X. Chen, Q. Zhang, W. Zhang, P. Li, L. Chen, Ecotoxicol. Environ. Saf. 175 (2019) 243–250. [127] M. Rahimnejad, R.A. Abdulkareem, G. Najafpour, Biocatal. Agric. Biotechnol. 20 (2019) 101245. [128] M. Asad, M.H. Sheikhi, M. Pourfath, M. Moradi, Sens. Actuators B 210 (2015) 1–8. [129] M. Annalakshmi, P. Balasubramanian, S.-M. Chen, T.-W. Chen, Microchim. Acta 186 (2019) 8. [130] X. Jiat, B. Yan, Z. Hiew, K. Chiew, L. Yee, S. Gan, S. Thangalazhy-gopakumar, S. Rigby, J. Taiwan Inst. Chem. Eng. 98 (2019) 163–180. [131] B.L. Dasari, J.M. Nouri, D. Brabazon, S. Naher, Energy 140 (2017) 766–778. [132] W. Li, X. Geng, Y. Guo, J. Rong, Y. Gong, L. Wu, X. Zhang, P. Li, J. Xu, G. Cheng, ACS Nano 5 (2011) 6955–6961. [133] B. Manna, C.R. Raj, ACS Sustain. Chem. Eng. 6 (2018) 6175–6182. [134] P. Noyrod, O. Chailapakul, W. Wonsawat, S. Chuanuwatanakul, J. Electroanal. Chem. 719 (2014) 54–59. [135] J. Zhang, Y. Zhang, J. Zhou, L. Wang, Anal. Chim. Acta 1043 (2018) 28–34. [136] J. Han, D. Zhao, D. Li, X. Wang, Z. Jin, K. Zhao, Polymers (Basel) 10 (2018) 31. [137] N. Jawahar, S.N. Meyyanathan, Int. J. Heal. Allied Sci. 1 (2012) 217. [138] S. Shrivastava, N. Jadon, R. Jain, Trends Anal. Chem. 82 (2016) 55–67. [139] R. Gangopadhyay, A. De, Chem. Mater. 12 (2000) 608–622. [140] L. Wei, L. Fan, H. Yang, Y. Wu, Int. J. Electrochem. Sci. 14 (2019) 10720–10728. [141] N. Prabhakar, H. Thakur, A. Bharti, N. Kaur, Anal. Chim. Acta 939 (2016) 108–116. [142] C. Duan, J. Zheng, Colloids Surf. A Physicochem. Eng. Asp. 567 (2019) 271–277. [143] X. Tan, Q. Hu, J. Wu, X. Li, P. Li, H. Yu, X. Li, F. Lei, Sens. Actuators B 220 (2015) 216–221. [144] E. Roy, S. Patra, R. Madhuri, P.K. Sharma, RSC Adv. 4 (2014) 56690–56700.

Advantages and limitations of functionalized nanomaterials based electrochemical sensors environmental monitoring

9

Balaji Maddiboyinaa, OmPrakash Sunaapub, Sandeep Chandrashekharappac, and Gandhi Sivaramand a Department of Pharmacy, Vishwabharathi College of Pharmaceutical Sciences, Guntur, Andhra Pradesh, India, bDepartment of Chemistry, University College of Engineering, Anna University, Dindigul, Tamil Nadu, India, cInstitute for Stem Cell Biology and Regenerative Medicine (InStem), Bangalore, Karnataka, India, dDepartment of Chemistry, Gandhigram Rural Institute Deemed University, Dindigul, Tamil Nadu, India

9.1 Introduction Chemistry is a branch of science concerned with substances of which matter is composed, investigation of their properties and reactions and the use of such reactions to form new substances. Physical chemistry is the study of macroscopic and particulate phenomenon in a chemical system in terms of principles, practices, and concept of physics such as motion, energy, force, time, thermodynamics, and chemical equilibriums and electrochemistry with other aspects [1–19]. Organic chemistry is the study of the structure, properties, composition reactions, and preparation of carbon-containing compounds [20–39]. In contemporary years, the advance of analytical techniques based on nanomaterials have emergent consideration for numerous submissions, comprising the vital biological exploration, monitoring of health, clinical diagnostics, pharmaceutical analysis, food safety, and environmental monitoring. Remaining with their remarkable physicochemical properties, high surface-to-volume ratio, great adsorption and responsive ability and other valuable properties not extant in the bulk materials, nanomaterials have acted as probable analytical probe to not only offer enriched sensitivity but also deliver a stair variation to analyze the single molecular realm [40]. Nanomaterials with distinctive functionalities and practices generate capable advancement of the novel analytical systems that are certainly elicited on exposure to initial chemical pollutants as well as real-time environmental monitoring in air, soil, and water and food safety based on how crucial it is to safeguard the environment and public health [41]. Nanomaterials have achieved extensive consideration as electrochemical-sensing constituents due to their astonishing properties, distinctive recital, and a wide range of constituents. The pervasive uses and solicitations of nanomaterials in electrochemical sensing are accompanying with their exceptional sorts of the large surface area, Functionalized Nanomaterial-Based Electrochemical Sensors. https://doi.org/10.1016/B978-0-12-823788-5.00016-8 Copyright © 2022 Elsevier Ltd. All rights reserved.

166

Functionalized Nanomaterial-Based Electrochemical Sensors

and exceptional mechanical, chemical, physical as well as electrical properties [42]. The large surface area plays a vital role in improving the kinetics of electrochemical reactions as well as providing a huge number of active sites for the chosen electrochemical reactivity [43]. Furthermore, nanomaterials can be auxiliary functionalized with preferred chemical moieties to improve the selectivity toward target analytes. The foremost group of tolerant chemicals that can be categorized majorly are heavy metals, inorganic anions, phenolic composites, pesticides and chemical warfare reagents, which can cumulatively source austere impairment to human health and environmental. Some of the pollutants are presumed of being cancer advocates and others have been accompanying with endocrine-disrupting effects via food chain [44]. An emergent range of sensors can have extensive impacts on the quality of everyday life. Sensors are usually poised of two parts: the receptor and the transducer. The receptor has high specificity, which can also significantly improve the detection sensitivity. The transducer is usually a distinct chemical or physical sense constituent, which works with electrochemical, optical, thermal, piezoelectric, and other detection principles. Notable issues to cogitate while assimilating any sensing platforms embrace cost-effectiveness, the probability for real-time monitoring in terms of sensitivity and selectivity, and chiefly the operational simplicity. In this concern, electrochemical sensors are among the encouraging technologies as they are simple, low-cost, sensitive, and selective substitutes of sophisticated instruments [45]. Diverse constituents have been used as modifiers for bare electrodes to improve their electrocatalytic action toward exposure of environmental pollutants. Over the recent decades, electrochemical sensor and biosensor platforms with the assimilation of nanostructured materials have immensely been engaged as prevailing analytical methods by appealing the benefit of easy-to-handle, cost-effective, highly sensitive and selective, rapid response, facile-to-fabricate and being portable [46]. Due to industrial revolution and urbanization, human environment is ruthlessly contaminated by inorganic and organic pollutants [47]. This contaminated environment poses serious health risks to human, wild life, and aquatic organisms. Various national and international environmental organizations have demarcated admissible limits of these toxic pollutants in diverse environmental partitions. Monitoring air, soil, and water for hazardous pollutants is vital and based on the prerequisite to safeguard the environment and public health from probable dispersal of natural and industrial inorganic and organic contaminants. There is a persistently increasing prerequisite for online monitoring of contaminants in our environment-driven new technologies. Pesticides (herbicides, fungicides, and insecticides) are extensively used in agriculture and industry. To limit their toxicity and their accrual in living organisms, dose adjustment and trace-level checking are desired. Thus, there is a crucial need to advance new methods for simple pesticide recognition at low concentrations, exclusively in the field [48]. A range of analytical instruments has been advanced over the years for fortitude of environmental pollutants. Despite their high sensitivity, selectivity, and efficiency, they are not appropriate for low-resources set up as their prices are too high to afford. Furthermore, analysis time is reliant on the nature and physical state of the matter. In the case of complex environmental illustrations, long and tedious sample practice is

Advantages and limitations of functionalized nanomaterials

167

vital. The prerequisite of the practiced expert and the high cost of consumables and routine upkeep also limits the scope of such devices in low-resource setups. Though extensive exertions have been made on reduction of such instruments, their convenience for field applications is a challenge. Consequently, simple, cost-effective, sensitive, selective, and portable instruments are essential to tackle the universal mandate for monitoring of environmental pollutants [49]. Electrochemical sensors can be a simple and low-cost substitute to the erudite instruments. The imperative enthusiasm of the design of the nanoscale electrode constituents is not only emphasizing on the indication extension via the catalytic action and conductivity, but also likely to deliver facile interactions with chemical and biological reagents and the immobilization of the functional moieties with accurately premeditated as signal tags, noticeable to highly selective sensing [50]. Thus, the construction of the functional nanoscale electrode materials is freshly evolving the wide environmental sensor applications (Fig. 9.1). For environmental monitoring, nanomaterials are frequently used in two diverse ways in constructing electrochemical sensors: (1) Together with an enzyme (enzymatic sensors) to increase the rate of electron transfer and to improve the sensitivity of the enzyme; or, (2) As individual catalysts (nonenzymatic sensors) to catalyze the reactions and to lower the limits of detection (LODs).

Further the advantages of the creation of functional nanocomposite-based sensor platforms, there are abundant characteristic drawbacks; comprising mass transport and electron transfer may be negatively compressed with efficient and stabilization molecules and the persistent existence of dissolution and accretion of nanomaterials. The development of nanocomposites or efficient nanocomposites unswervingly grown on the electrode surface is a capable resolution for the exceeding discussed difficulties, as suggested by Govindhan et  al. [51,52]. These obligatory necessities should be inherent while manipulating the electrode materials. The upward of progressive ­nanomaterials-based electrochemical sensor platforms begins a very effective

Othe

r nan (Fe O omateria ls 2 , TiO 3)

Ca rbo (C n-ba NT se s, G d m rap ate he rial nc ) s

Nanomaterials

In wa dus ste tria wa l ter

To (N xic Ox ga , S ses O 2)

Applications

Environmental monitoring

Or ga no pe pho sti sp cid h es oru s

Fig. 9.1  Nanomaterials-based sensor for environmental monitoring.

He a (H vy m g 2+ e , P tal i b 2+ on ) s

m dots Quantu dTe) C (CdSe.

s ticle par ) ano gNPs ic n tall PS, A N (Au

Me

als ateri sed m ays) n-ba rr Silico Ws or a (SIN

168

Functionalized Nanomaterial-Based Electrochemical Sensors

and vigorous research field that may be predicted to offer next cohort electrochemical technologies for environmental analyses. A varied extending effort has been made on the extension of electrochemical sensors and biosensors based on the functional nanostructured electrode provisions, united with innumerable electroanalytical techniques, progressing the extensive environmental applications [53,54].

9.2 Advantages Numerous investigation assemblies have intricate lecturing numerous concerns on the progress of the nanomaterials for electrochemical sensor engaged for the environmental sensor applications. ●























The integrations of the dimensional, compositional, geometric, and structural properties of nanomaterials are vital to convey exceptional functionality and stuff of the nanomaterials. The adsorption and interaction of the nanomaterials with chemical or biomolecules are key substantial on the fabrication of nanomaterials for catalysis and sensor applications [55]. The controlled size and composition, interfaces and distributions, nucleation and growth, stability, scale-up synthesis and assembly strategies for low-cost, large-scale production are main concerns of the synthesis of the nanomaterials [56]. There are numerous nanomaterials and their nanocomposites have employed for the environmental sensor applications because of various attractive characteristics, including high-chemical (bio) compatibility and inertness, easy to functionalize, huge surface energy and great electrode kinetics [57]. The physical and catalytic properties of the nanomaterials can be easily tuned or altered by the reduction of the spatial dimension or the confinement of the structures in a precise crystallographic direction. The properties of the nanomaterials are mainly associated to different origins via large fraction of surface atoms, large surface energy, spatial confinement, and the reduced imperfections. These can be tuned simply by adjusting the size, shape, or extent of agglomeration [58]. The electrical conductivity decreases by increased surface scattering. The mechanism of electrical conductivity on the thin film can be extensively explained by a simple tunneling between localized insulating states, which imply a high resistivity at low temperatures [59]. In environmental monitoring, enzyme-based or protein-based nanomaterials sensors have mostly been prepared for detection of pesticides (e.g., phenolic compounds) or NOx compounds. Sensors based on nanoscale metal oxide semiconductors such as SnO2, In2O3, ZnO, TiO2, WO3, and NiO play an important role in the environmental monitoring of explosive/toxic gases and volatile organic compounds (VOCs). A direct robust As (III) sensor using zirconia-nanocubes-modified gold electrode. Based on the electrochemical oxidation behavior of As, the sensing was achieved by cyclic voltammetry (CV) and chronoamperometry (CA) with an ultra-sensitivity of 550 nA cm−  2 ppb−  1, a detection limit of 5 ppb, and a wide linear range of 5–60 ppb with a response time of