Soft Electronics for Diagnosis, Therapy, and Integrated Systems

Xinge Yu is an Associate Professor in the Department of Biomedical Engineering at the City University of Hong Kong.Jiyu Li is a Postdoctoral Fellow in the Department of Biomedical Engineering at City University of Hong Kong.Ya Huang is a Postdoctoral Fellow in the Department of Biomedical Engineering at City University of Hong Kong.Enming Song is pursuing a PhD degree in materials science at Fudan University, Shanghai, China.

• Preface xiiiSession I Soft Sensors for Diagnosis 11 Mechanics Design of Flexible Sensors 3li Yuhang, Zhao Zhao, and Wu Wenbin1.1 Design of Stretchable Flexible Device Structure 31.1.1 Ripple Method 31.1.2 Island Bridge Structure-Curved Line 121.1.3 Island Bridge Structure-Serpentine Line 151.1.4 2D Spiral Interconnects 261.1.5 3D Spiral Interconnects 321.1.6 2D Fractal Structure 351.2 Structural Design of Substrate 381.2.1 Surface Structure Designs 391.2.2 Cellular Substrate Designs 401.2.3 Curvilinear Substrate Designs 431.3 Structural Designs for Spatial Integration of Device Systems 451.3.1 Strategy of Folding-Based Origami 451.3.2 Strategy of Buckling-Guided 3D Assembly 511.3.3 Stacked Multilayer Designs 57References 592 Epidermal Wearable Biosensors 67Xingcan Huang, Yanli Jiao, Yawen Yang, and Jiyu li2.1 Wearable Biosensing Technology 672.1.1 History of Wearable Biosensors 672.1.2 Wearable Enzymatic Biosensors 682.1.3 Wearable Immunosensors 692.1.4 Wearable Ion Biosensors 702.2 Epidermal Wearable Biosensors 732.2.1 Introduction 732.2.2 Flexible and Stretchable Epidermal Sensors 742.2.3 Self-powered Sweat Sensors 762.3 Ocular Wearable Sensors 792.3.1 Ocular Biomarkers 792.3.2 Wearable Ocular Sensors 802.3.2.1 Contact Lens Sensor 812.3.2.2 Capsule-based Tear Sensors 872.3.2.3 Wearable Eye Patch 872.3.2.4 Eyeglass Sensor 882.3.3 Conclusion 882.4 Wound Sensor 88List of Abbreviations 91References 923 Soft Sensors for Disease Diagnosis 101Huihui Hu, Yuyan Su, and Kewang Nan3.1 Introduction 1013.2 Materials and Structures of Flexible Sensors 1033.2.1 Materials 1033.2.1.1 Nanomaterials 1033.2.1.2 Liquid Conductors 1053.2.1.3 Elastomer 1063.2.1.4 Conductive Polymer 1063.2.1.5 Hydrogel 1073.2.1.6 Textile 1083.2.2 Structures 1093.2.2.1 Serpentine Structure 1093.2.2.2 Mesh Structure 1103.2.2.3 Kirigami Structure 1113.2.2.4 Fractal Structure 1123.2.2.5 Coiled Structure 1123.2.2.6 Wave Structure 1133.2.2.7 Three-Dimensional Porous Structure 1143.3 Application of Flexible Sensors in Disease Diagnosis 1143.3.1 Diagnosis of Cardiovascular Diseases 1153.3.1.1 Heart Rate 1153.3.1.2 Blood Pressure 1173.3.1.3 Blood Oxygen Saturation 1173.3.2 Diagnosis of Brain Disease 1183.3.2.1 Soft Sensor Materials for Brain Interfaces 1193.3.2.2 Applications 1213.3.3 Diagnosis and Self-management of Chronic Disease 1233.3.3.1 Flexible Sensors for Diabetes 1233.3.3.2 Flexible Sensors for Chronic Inflammatory Diseases 1253.3.3.3 Flexible Sensors for Chronic Respiratory Diseases 1263.3.3.4 Flexible Sensors for Cancers 127List of Abbreviations 128References 1294 Wearable Chemical Sensors for Noninvasive Monitoring 147Hnin Yin Yin Nyein, Asmita Veronica, Yanan Li, and Yue Guo4.1 Introduction 1474.2 Biofluids of Interest for Wearable Chemical Sensors 1504.2.1 Dermal Biofluids 1534.2.1.1 Sweat 1534.2.1.2 Interstitial Fluid 1554.2.2 Oral Biofluids 1574.2.2.1 Saliva 1574.2.2.2 Gcf 1604.3 Biofluid Enabled Platforms: Traditional to Wearable 1614.3.1 Need for Noninvasive Wearable Chemical Sensing 1614.3.2 Potential Challenges in Wearable Chemical Sensors 1624.4 Sampling and Detection Strategies for Biofluid-Based Wearable Sensors 1634.4.1 Sweat Sampling and Induction Methods 1634.4.2 ISF Sampling Methods 1654.4.3 Saliva Sampling Methods 1684.4.4 Detection Mechanisms for Noninvasive Wearable Sensors 1694.5 Outlook 172References 1745 Flexible Electrode for Noninvasive Brain–Computer Interfaces 181Sen Lin5.1 Introduction 1815.2 Development of Noninvasive BCIs 1825.3 Electrode Technologies for Noninvasive BCIs 1835.3.1 Rigid Electrodes 1835.3.1.1 Wet Electrodes 1845.3.1.2 Dry Electrode 1845.3.2 Flexible Electrodes 1865.3.2.1 Flexible Dry Electrodes 1865.3.2.2 Semi-dry Electrode 1895.4 Challenges 1915.5 Conclusion 193References 1946 Chronic Neural Interfaces 203Enming Song, Yifei Lu, and Hehua Zhang6.1 Introduction 2036.2 Architectures for Mechanical Compliance and Biocompatibility 2046.3 Advanced Chronically Stable Materials for Neural Interfaces 2096.4 Encapsulation for Stable Operation 2116.5 Engineering Strategies for Chronic Active Sensing 2206.6 Multimodal Functions of Long-Term Stable Implants 2256.7 Challenges and Future Directions 228References 2297 Mechanical Sensors (Transducers) for Motion Detection of Humans and Organs 235Chengfeng Pan7.1 Introduction 2357.2 Classification of Stretchable Mechanical Sensors 2367.2.1 Resistive Sensors 2367.2.2 Capacitive Sensors 2367.2.3 Piezoelectric Sensors 2377.2.4 Triboelectric Sensors 2377.2.5 Electromagnetic Sensors 2387.3 Material Architectures 2387.3.1 Flexible/Stretchable Matrix Materials 2397.3.2 Electrically Conductive Materials 2417.4 Sensing Mechanisms 2447.4.1 Geometrical Effect 2447.4.2 Piezoresistive Effect 2457.4.3 Disconnection Mechanism 2467.4.4 Crack Propagation 2477.4.5 Tunneling Effect 2477.5 Representative Applications 2487.5.1 Small Strain Detection 2487.5.2 Large Motion Monitoring 250References 2528 Smart Optoelectronics in Health Monitoring and Human-Machine Interactions 257Leilei Gu, Yuanjing Lin, and Qianpeng Zhang8.1 Fundamentals on Photodetectors 2578.1.1 Figures-of-Merit of Photodetectors 2578.1.2 Classification of Photodetectors 2598.1.3 Material Advances in Photodetectors 2618.1.3.1 2D Materials 2628.1.3.2 Quantum Dots 2628.1.3.3 Perovskites and Other Organic Materials 2638.1.3.4 Nanostructure-based Photodetectors 2648.2 Integrated Optoelectronic Systems 2648.2.1 Integration of Photodetectors with LEDs 2668.2.2 Photodetectors Integrated with Energy Storage Devices 2678.2.3 Self-powered Optoelectronic Systems 2688.2.4 Integration Strategies 2708.3 Flexible Integrated Systems Based on Photodetectors for Advanced Applications 2738.3.1 Clinical Diagnostic 2738.3.1.1 Lab-on-a-Chip Systems for Diagnostics 2738.3.1.2 Wearable Biosensing for Daily Health Monitoring 2758.3.1.3 Optoelectronics for Advanced Human-Machine Interaction 2778.3.1.4 Autopilot Systems 2808.4 Future Trend of Photodetectors for Soft Electronics 282References 2839 Wearable Sensor for Bioimaging 287Cunman Liang, Zhou Jiang, Ni Zhao, Puxiang Lai, and Yingying Zhou9.1 Introduction 2879.2 Wearable Ultrasound Bioimaging Sensor 2889.2.1 Overall Description 2889.2.2 Imaging Principles 2899.2.3 Structures and Materials 2909.2.4 Typical Devices and Applications 2929.2.4.1 1D Transducer Array 2929.2.4.2 2D Transducer Array 2949.2.4.3 Orthogonal Transducer Array 2969.2.5 Summary 2989.3 Wearable Photoacoustic Imaging Sensor 2999.3.1 Overall Description 2999.3.2 Imaging Principles 2999.3.3 Structures and Materials 3019.3.4 Typical Devices and Applications 3029.3.5 Summary 3049.4 Wearable Electrical Impedance Tomography 3059.4.1 Overall Description 3059.4.2 Imaging Principles 3059.4.3 Structures and Materials 3069.4.4 Typical Devices and Applications 3079.4.4.1 Pulmonary Imaging 3079.4.4.2 Cancer Detection 3099.4.4.3 Gesture Recognition 3109.4.5 Summary 3129.5 Wearable Terahertz Imaging Sensor 3129.5.1 Overall Description 3129.5.2 Imaging Principles 3139.5.3 Structures and Materials 3139.5.4 Typical Devices and Applications 3149.5.5 Summary 3169.6 Wearable Bioimaging Device for Biomedical Applications 3169.6.1 Ultrasound Imaging 3169.6.2 Photoacoustic Imaging 3279.7 Conclusion 329References 330Session II Soft Sensors for Therapy 33310 Thermotherapy (Resistive Heaters, Photothermal Nanomaterials, Textile Devices, Cryotherapy, etc.) 335Xiao Yang and Zuankai Wang10.1 Introduction 33510.2 Resistive Heaters 33610.2.1 Metal Wire 33610.2.2 Two-Dimensional (2D) Materials 33910.2.3 Conductive Polymers 34110.2.4 Conclusion 34310.3 Photothermal Nanomaterials 34310.4 Textile Devices 34810.5 Cryotherapy 354List of Abbreviations 355References 35611 Soft Electronics for Drug Delivery 361Lelun Jiang and Jingbo Yang11.1 Introduction 36111.2 Skin Structure 36211.3 Soft Electronics-Assisted TTDS for Drug Delivery 36411.3.1 MNs for Passive Drug Delivery 36411.3.2 Soft Electronics-MNs Systems for Active Drug Delivery 36711.3.3 Soft Electronics-MN Systems for Closed-Loop Drug Delivery 37211.3.4 Soft Electronic Systems for Closed-Loop Drug Delivery 37511.4 Conclusions and Perspectives 379List of Abbreviations 380References 38012 Wearable and Implantable Drug Delivery System 387Xinran Jiang, Han Wu, Ao Xiao, Ya Huang, Xinge Yu, and Lingqian Chang12.1 Introduction 38712.2 Categories of Soft Electronics for Drug Delivery 38912.2.1 Wearable Systems 39012.2.2 Implantable Systems 39412.3 Challenges and Prospects 399References 40013 Soft Robotic Sensing and Medicine 403Dengfeng li13.1 Introduction 40313.2 Soft Robotic Tactile Sensing 40313.3 Soft Robotic Environmental Sensing 40613.4 Miniature Robotic In Vivo Medicine 409References 410Session III Soft Sensors for Interaction 41514 Integration System 417Chun Ki Yiu, Pengcheng Wu, Jingkun Zhou, and Park Wooyoung14.1 Power Supply Strategy of Soft Electronics 41714.1.1 Introduction 41714.1.2 Power Source 41814.1.3 Regulation 41914.2 Encapsulation 42214.3 Communication 42414.4 Closed-Loop Control (AI, Deep Learning, Microcontroller Unit, etc.) 427List of Abbreviations 432References 43215 Self-powered Sensors 437Binbin Zhang and Zhiming Lin15.1 Introduction 43715.2 Piezoelectric Sensor 43915.3 Triboelectric Sensor 44115.4 Piezoionic Sensor 44515.5 Electromagnetic Sensor 44615.6 Thermoelectric Sensors 44815.7 Potentiometric Ion Sensors 45315.8 Conclusion 455References 457Index 461