Wearable Physical, Chemical and Biological Sensors: Fundamentals, Materials and Applications

Description

Wearable Physical, Chemical and Biological Sensors introduces readers of all backgrounds―chemistry, electronics, photonics, biology, microfluidics, materials, and more―to the fundamental principles needed to develop wearable sensors for a host of different applications. The capability to continuously monitor organ-related biomarkers, environmental exposure, movement disorders, and other health conditions using miniaturized devices that operate in real time provides numerous benefits, such as avoiding or delaying the onset of disease, saving resources allocated to public health, and making better decisions on medical diagnostics or treatment. Worn like glasses, masks, wristwatches, fitness bands, tattoo-like devices, or patches, wearables are being boosted by the Internet of Things in combination with smart mobile devices. Besides, wearables for smart agriculture are also covered. Written by experts in their respective fields, Wearable Physical, Chemical and Biological Sensors provides insights on how to design, fabricate, and operate these sensors.    Contributors Contents Dedication Chapter 1 - Introduction Chapter 2 - Materials for wearable sensors 2.1 Introduction 2.2 Materials for wearable (bio)sensors 2.2.1 Designing a wearable (bio)sensor 2.2.2 Substrate materials 2.2.3 Nanomaterial integration for tailored substrate materials 2.2.4 Natural biopolymers 2.3 Functionalization of substrate materials 2.4 Wearables sensors for noninvasive healthcare monitoring 2.5 Conclusion and future perspectives Declaration of conflict of interest Acknowledgments List of acronyms References Chapter 3 - Biorecognition elements 3.1 Introduction 3.2 Biorecognition elements in wearable biosensors 3.2.1 Antibodies 3.2.2 Enzymes 3.2.3 Nucleic acid-based recognition elements 3.2.4 Other biorecognition elements 3.2.4.1 Aptamers 3.2.4.2 Affimers 3.2.4.3 CRISPR/Cas 3.2.4.4 Molecularly imprinted polymers 3.2.4.5 Nanozymes 3.2.4.6 Lectin as biorecognition elements 3.3 Immobilization strategies for biorecognition elements 3.3.1 Covalent binding 3.3.2 Crosslinking 3.3.3 Entrapment 3.3.4 Adsorption 3.3.5 Affinity binding 3.3.5.1 Biotin-avidin interaction 3.3.5.2 Antibody-binding proteins 3.4 Applications of wearable biosensors for monitoring body fluids 3.4.1 Sweat 3.4.2 Saliva 3.4.3 Tear 3.5 Current challenges and prospects Declaration of conflict of interest List of acronyms References Chapter 4 - Signal detection techniques 4.1 Introduction 4.2 Signal transduction in wearable sensors 4.3 Optical detection 4.3.1 Photoplethysmography 4.3.2 Colorimetric detection 4.3.3 Fluorescence detection 4.4 Electrical and electrochemical detection 4.4.1 Electrodes: Fabrication and materials 4.4.2 Electrical/electrochemical detection techniques 4.4.2.1 Potentiometric detection 4.4.2.2 Amperometric detection 4.4.2.3 Voltammetric detection 4.4.2.4 Field-effect transistors-based detection 4.4.3 Multimodal detection 4.5 Conclusions and outlook List of acronyms Acknowledgments References Chapter 5 - Signal enhancement strategies 5.1 Introduction 5.2 Part A—Sample collection via microfluidics 5.3 Fabrication techniques of microfluidic structures 5.3.1 Soft lithography 5.3.2 Wax printing on cellulose-based materials 5.3.3 3-D printing/additive approaches 5.4 Membranes 5.5 Sampling for wearable sensing 5.6 Challenges and future perspectives 5.7 Part B—Nanomaterial-based signal amplification strategies 5.8 Definition 5.9 History 5.10 Features for sensing 5.11 Classification and examples (0-D/1-D/2-D/3-D nanomaterials) 5.11.1 0-D nanomaterials (0DNMs) 5.11.2 1-D nanomaterials (1DNMs) 5.11.3 2-D nanomaterials (2DNMs) 5.11.4 3-D nanomaterials (3DNMs) 5.12 Nanomaterials enhanced strategy 5.12.1 Physical sensors 5.12.2 (Bio)chemical sensors 5.13 Conclusions and future perspectives Acknowledgments References Chapter 6 - Healthcare data analytics for wearable sensors 6.1 Introduction 6.2 Machine learning at the edge 6.3 Uncertainties in healthcare data 6.4 Data analysis in healthcare using Big Data 6.5 Algorithmic approach for data storage and access 6.6 Signal conditioning, wireless communication, and regulatory landscape 6.7 Conclusion and outlook Acknowledgments References Chapter 7 - Wearable physical sensors 7.1 Introduction 7.2 Self-powered wearable physical sensors 7.2.1 Triboelectric nanogenerators 7.2.1.1 Vertical contact-separation mode 7.2.1.2 Lateral sliding mode 7.2.1.3 Single-electrode mode 7.2.1.4 Free-standing triboelectric layer mode 7.2.2 TENG-based physiological sensors 7.2.2.1 Respiratory monitoring 7.2.2.2 Cardiovascular monitoring 7.2.2.3 Motion monitoring 7.2.3 Piezoelectric nanogenerators 7.2.3.1 Introduction to piezoelectricity 7.2.3.2 AC PENGs 7.2.3.3 DC PENGs 7.2.3.4 Noncontact AC PENGs 7.2.4 PENG-based physiological sensors 7.2.4.1 Cardiovascular monitoring 7.2.4.2 Motion monitoring 7.2.4.3 Voice recognition 7.2.4.4 Dermal sensing 7.2.4.5 Gastrointestinal sensing 7.3 Non-self-powered wearable physical sensors 7.3.1 Capacitive 7.3.1.1 Working principle 7.3.1.2 Applications 7.3.2 Electret 7.3.2.1 Working principle 7.3.2.2 Applications 7.3.3 Field-effect transistor (FET) 7.3.3.1 Working principle 7.3.3.2 FET applications 7.3.4 Resistive 7.3.4.1 Working principle 7.3.4.2 Applications 7.4 Conclusions and future perspectives Acknowledgments References Chapter 8 - Wearable chemosensors 8.1 Introduction 8.2 Chemical biomarkers 8.3 Analytical parameters 8.4 Intrinsic challenges of wearable chemosensors 8.5 Wearable platforms 8.5.1 Sweat sensors 8.5.2 Saliva sensors 8.5.3 Interstitial fluid sensors 8.5.4 Tear sensors 8.6 System integration 8.7 Conclusions Acknowledgments List of acronyms References Chapter 9 - Wearable Biosensors 9.1 Introduction 9.2 Noninvasive biosensing: eccrine sweat 9.2.1 Sweat as a biofluid source of analytes 9.2.2 Sweat biosensing devices 9.3 Minimally invasive biosensing: dermal ISF 9.3.1 ISF as a biofluid source of analytes 9.3.2 ISF biosensing devices 9.4 Noninvasive biosensing: other body fluids and sources 9.4.1 Saliva, exhaled breath, and tears 9.5 Current challenges and outlook References Chapter 10 - Wearable hybrid sensors 10.1 Introduction 10.2 Flexible and stretchable materials 10.3 Electrically conducting materials 10.4 Strategies to manufacture wearable systems 10.5 Applications 10.5.1 Biophysical integrative applications 10.5.2 Biochemical integrative applications 10.5.3 Exploring further applications 10.6 Conclusions and outlook References Chapter 11 - Smart-agriculture: wearable devices for plant protection 11.1 Introduction 11.2 Wearable devices for monitoring plant status under stress 11.3 Wearable devices for detecting pesticides from agricultural products and environment 11.3.1 Wearable electrochemical devices 11.3.2 Wearable spectroscopy-based devices 11.3.3 Wearable colorimetric devices 11.4 Current challenges and conclusion Acknowledgments Abbreviations References Chapter 12 - Internet of wearable things 12.1 Wearables and Internet of Things 12.2 Toward IoWT 12.3 Concluding remarks and future perspectives References Index