Progress and challenges in fabrication of wearable sensors for health monitoring

Abstract Rapid development in sensor technology, has led to fabrication of high-performance wearable sensors with application in human health monitoring. As human health is an utmost importance issue, various high-tech equipment has been developed to use in continuous health monitoring. The favorable properties of wearable sensors, make them an appropriate choice in medical applications. In this context, wearable sensors designed, produced and utilized in human health care systems which can facilitate diseases diagnosis. Depend on the type of sensor, a specific parameter such as heart beat, pressure, and temperature can be monitored and measured. This review attempts to summarize the progress and challenges in fabrication of wearable sensors for human health monitoring. In this context, applications of wearable sensors are divided into (a) biophysical tracking, (b) biochemical monitoring, and (c) detection of real-time data. Moreover, details of medical wearable sensors are outlined. In this regard, types of sensors, their materials and fabrication processes are explained. Finally, performance and current challenges in this field are briefly discussed. The documented analysis and discussion in this paper show the advantages and limitations in this field, and also highlight needs for next researches. This review confirmed that the emergence of wearable sensors has opened new horizons for human health monitoring.

[1]  Hiroyuki Matsui,et al.  Noninvasive Sweat-Lactate Biosensor Emplsoying a Hydrogel-Based Touch Pad , 2019, Scientific Reports.

[2]  Deepak Ganesan,et al.  Fabric as a Sensor: Towards Unobtrusive Sensing of Human Behavior with Triboelectric Textiles , 2018, SenSys.

[3]  Li Niu,et al.  A multichannel electrochemical all-solid-state wearable potentiometric sensor for real-time sweat ion monitoring , 2019, Electrochemistry Communications.

[4]  Anthony Turner,et al.  Biosensors: then and now. , 2013, Trends in biotechnology.

[5]  Guang-Zhong Yang,et al.  A wearable multisensing patch for continuous sweat monitoring. , 2017, Biosensors & bioelectronics.

[6]  Hye Rim Cho,et al.  Wearable/disposable sweat-based glucose monitoring device with multistage transdermal drug delivery module , 2017, Science Advances.

[7]  Yue Li,et al.  Flexible and wearable healthcare sensors for visual reality health-monitoring , 2019, Virtual Real. Intell. Hardw..

[8]  Yang Gao,et al.  Highly Stretchable and Self‐Healable MXene/Polyvinyl Alcohol Hydrogel Electrode for Wearable Capacitive Electronic Skin , 2019, Advanced Electronic Materials.

[9]  Chenyang Xue,et al.  Flexible one-structure arched triboelectric nanogenerator based on common electrode for high efficiency energy harvesting and self-powered motion sensing , 2018 .

[10]  Kim-Kwang Raymond Choo,et al.  A smartphone-based wearable sensors for monitoring real-time physiological data , 2017, Comput. Electr. Eng..

[11]  J. Windmiller,et al.  Electrochemical tattoo biosensors for real-time noninvasive lactate monitoring in human perspiration. , 2013, Analytical chemistry.

[12]  Ali Javey,et al.  A Wearable Microfluidic Sensing Patch for Dynamic Sweat Secretion Analysis. , 2018, ACS sensors.

[13]  Johannes Peltola,et al.  Activity classification using realistic data from wearable sensors , 2006, IEEE Transactions on Information Technology in Biomedicine.

[14]  Dermot Diamond,et al.  A wearable electrochemical sensor for the real-time measurement of sweat sodium concentration , 2010 .

[15]  Debes Bhattacharyya,et al.  Highly stretchable and wearable strain sensors using conductive wool yarns with controllable sensitivity , 2019, Sensors and Actuators A: Physical.

[16]  Hongnian Yu,et al.  A practical multi-sensor activity recognition system for home-based care , 2014, Decis. Support Syst..

[17]  Jingmin Fan,et al.  Highly conductive, washable and super-hydrophobic wearable carbon nanotubes e-textile for vacuum pressure sensors , 2020 .

[18]  Zong-Hong Lin,et al.  A textile-based triboelectric nanogenerator with humidity-resistant output characteristic and its applications in self-powered healthcare sensors , 2018, Nano Energy.

[19]  Zhiming Lin,et al.  Large‐Scale and Washable Smart Textiles Based on Triboelectric Nanogenerator Arrays for Self‐Powered Sleeping Monitoring , 2018 .

[20]  Hye Rim Cho,et al.  A graphene-based electrochemical device with thermoresponsive microneedles for diabetes monitoring and therapy. , 2016, Nature nanotechnology.

[21]  Liang Dong,et al.  Helical-Shaped Graphene Tubular Spring Formed Within Microchannel for Wearable Strain Sensor With Wide Dynamic Range , 2017, IEEE Sensors Letters.

[22]  Pukar Maharjan,et al.  An impedance tunable and highly efficient triboelectric nanogenerator for large-scale, ultra-sensitive pressure sensing applications , 2018, Nano Energy.

[23]  Mehmet Rasit Yuce,et al.  A chest-based continuous cuffless blood pressure method: Estimation and evaluation using multiple body sensors , 2020, Inf. Fusion.

[24]  Jae Hyeon Park,et al.  A flexible, ultra-sensitive chemical sensor with 3D biomimetic templating for diabetes-related acetone detection. , 2017, Journal of materials chemistry. B.

[25]  Hongnian Yu,et al.  An Automatic Gait Feature Extraction Method for Identifying Gait Asymmetry Using Wearable Sensors , 2018, Sensors.

[26]  Ivana Murković Steinberg,et al.  Wireless chemical sensors and biosensors: A review , 2018, Sensors and Actuators B: Chemical.

[27]  J. Kofman,et al.  Review of fall risk assessment in geriatric populations using inertial sensors , 2013, Journal of NeuroEngineering and Rehabilitation.

[28]  Seok Hyun Yun,et al.  Contact Lens Sensors in Ocular Diagnostics , 2015, Advanced healthcare materials.

[29]  Xiaosheng Fang,et al.  High-Performance Silicon-Compatible Large-Area UV-to-Visible Broadband Photodetector Based on Integrated Lattice-Matched Type II Se/n-Si Heterojunctions. , 2018, Nano letters.

[30]  Zhongze Gu,et al.  Wearable eye health monitoring sensors based on peacock tail-inspired inverse opal carbon , 2019 .

[31]  Fu-Kuo Chang,et al.  A Spider‐Web‐Like Highly Expandable Sensor Network for Multifunctional Materials , 2010, Advanced materials.

[32]  Amay J Bandodkar,et al.  Non-invasive wearable electrochemical sensors: a review. , 2014, Trends in biotechnology.

[33]  Philipp Gutruf,et al.  Transparent functional oxide stretchable electronics: micro-tectonics enabled high strain electrodes , 2013 .

[34]  Sudha Ramasamy,et al.  Wearable sensors for ECG measurement: a review , 2018, Sensor Review.

[35]  Yu Jiang,et al.  Wearable biomolecule smartsensors based on one-step fabricated berlin green printed arrays. , 2019, Biosensors & bioelectronics.

[36]  A. Pourkamali Anaraki,et al.  Highly sensitive and stretchable strain sensors based on chopped carbon fibers sandwiched between silicone rubber layers for human motion detections , 2020, Journal of Composite Materials.

[37]  Ju-Won Jeon,et al.  Ultrastretchable Conductive Polymer Complex as a Strain Sensor with a Repeatable Autonomous Self-Healing Ability. , 2019, ACS applied materials & interfaces.

[38]  Woo Y. Lee,et al.  Fabric-infused array of reduced graphene oxide sensors for mapping of skin temperatures , 2018, Sensors and Actuators A: Physical.

[39]  Sepehr Nesaei,et al.  Micro additive manufacturing of glucose biosensors: A feasibility study. , 2018, Analytica chimica acta.

[40]  Joseph Wang,et al.  Wearable Electrochemical Sensors and Biosensors: A Review , 2013 .

[41]  Cylinder-shaped thermal inertial force sensor for wearable fabric sensor systems , 2011, 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference.

[42]  J Heikenfeld,et al.  Complete validation of a continuous and blood-correlated sweat biosensing device with integrated sweat stimulation. , 2018, Lab on a chip.

[43]  John A Rogers,et al.  Wearable Sensors for Biochemical Sweat Analysis. , 2019, Annual review of analytical chemistry.

[44]  Xiang Ma,et al.  A Highly Sensitive Nonenzymatic Glucose Biosensor Based on the Regulatory Effect of Glucose on Electrochemical Behaviors of Colloidal Silver Nanoparticles on MoS2 † , 2016, Sensors.

[45]  Fabrication of organic flexible electrodes using transfer stamping process , 2009 .

[46]  Hristijan Gjoreski,et al.  Activity/Posture Recognition using Wearable Sensors Placed on Different Body Locations , 2011 .

[47]  Goangseup Zi,et al.  Stretchable Active Matrix Temperature Sensor Array of Polyaniline Nanofibers for Electronic Skin , 2016, Advanced materials.

[48]  N. Wu,et al.  Selective stamp bonding of PDMS microfluidic devices to polymer substrates for biological applications , 2013 .

[49]  Zisheng Xu,et al.  Hierarchical elastomer tuned self-powered pressure sensor for wearable multifunctional cardiovascular electronics , 2020 .

[50]  Seung-Hwan Chang,et al.  Smart-fabric sensor composed of single-walled carbon nanotubes containing binary polymer composites for health monitoring , 2018 .

[51]  Xue Feng,et al.  Breathable and Stretchable Temperature Sensors Inspired by Skin , 2015, Scientific Reports.

[52]  T. Someya,et al.  Conformable, flexible, large-area networks of pressure and thermal sensors with organic transistor active matrixes. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[53]  Kyoung G. Lee,et al.  Highly self-healable and flexible cable-type pH sensors for real-time monitoring of human fluids. , 2020, Biosensors & bioelectronics.

[54]  M. Shikida,et al.  Fabrication of a wearable fabric tactile sensor produced by artificial hollow fiber , 2008 .

[55]  Sangwoo Jin,et al.  Stretchable Array of Highly Sensitive Pressure Sensors Consisting of Polyaniline Nanofibers and Au-Coated Polydimethylsiloxane Micropillars. , 2015, ACS nano.

[56]  Yonggang Huang,et al.  Stretchable and Foldable Silicon Integrated Circuits , 2008, Science.

[57]  Somayeh Imani,et al.  Eyeglasses based wireless electrolyte and metabolite sensor platform. , 2017, Lab on a chip.

[58]  C.C.Y. Poon,et al.  A Health-Shirt using e-Textile Materials for the Continuous and Cuffless Monitoring of Arterial Blood Pressure , 2006, 2006 3rd IEEE/EMBS International Summer School on Medical Devices and Biosensors.

[59]  Sam Emaminejad,et al.  A Wearable Electrochemical Platform for Noninvasive Simultaneous Monitoring of Ca(2+) and pH. , 2016, ACS nano.

[60]  Xueguang Yuan,et al.  Human motion monitoring in sports using wearable graphene-coated fiber sensors , 2018 .

[61]  Toshiya Arakawa,et al.  Recent Research and Developing Trends of Wearable Sensors for Detecting Blood Pressure , 2018, Sensors.

[62]  Zhiyong Fan,et al.  A Wearable Sweat Band for Noninvasive Levodopa Monitoring. , 2019, Nano letters.

[63]  Geun Yeol Bae,et al.  Linearly and Highly Pressure‐Sensitive Electronic Skin Based on a Bioinspired Hierarchical Structural Array , 2016, Advanced materials.

[64]  Donald P. Butler,et al.  MEMS Force Sensor in a Flexible Substrate Using Nichrome Piezoresistors , 2013, IEEE Sensors Journal.

[65]  Sam Emaminejad,et al.  Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis , 2016, Nature.

[66]  Ahmad Almogren,et al.  A robust human activity recognition system using smartphone sensors and deep learning , 2018, Future Gener. Comput. Syst..

[67]  Zheng Lou,et al.  Bio‐Multifunctional Smart Wearable Sensors for Medical Devices , 2019, Adv. Intell. Syst..

[68]  Tan Nhiem Ly,et al.  Wearable strain sensor for human motion detection based on ligand-exchanged gold nanoparticles , 2020 .

[69]  Eirini Velliou,et al.  Development of a novel highly conductive and flexible cotton yarn for wearable pH sensor technology , 2019, Sensors and Actuators B: Chemical.

[70]  B. Tang,et al.  Multiscale Humidity Visualization by Environmentally Sensitive Fluorescent Molecular Rotors , 2017, Advanced materials.

[71]  Lijie Sun,et al.  Ionogel-based, highly stretchable, transparent, durable triboelectric nanogenerators for energy harvesting and motion sensing over a wide temperature range , 2019, Nano Energy.

[72]  Alex Chortos,et al.  A Sensitive and Biodegradable Pressure Sensor Array for Cardiovascular Monitoring , 2015, Advanced materials.

[73]  B. Shi,et al.  Collagen-based breathable, humidity-ultrastable and degradable on-skin device , 2019, Journal of Materials Chemistry C.

[74]  Pierluigi Ritrovato,et al.  An edge-stream computing infrastructure for real-time analysis of wearable sensors data , 2019, Future Gener. Comput. Syst..

[75]  Chengkuo Lee,et al.  Self-Powered and Self-Functional Cotton Sock Using Piezoelectric and Triboelectric Hybrid Mechanism for Healthcare and Sports Monitoring. , 2019, ACS nano.

[76]  Md Maksudul Hossain,et al.  Piezoresistive Graphene/P(VDF-TrFE) Heterostructure Based Highly Sensitive and Flexible Pressure Sensor. , 2019, ACS applied materials & interfaces.

[77]  Dhruv R. Seshadri,et al.  Wearable sensors for monitoring the internal and external workload of the athlete , 2019, npj Digital Medicine.

[78]  Yael Hanein,et al.  Carbon Nanotube-Based Ion Selective Sensors for Wearable Applications. , 2017, ACS applied materials & interfaces.

[79]  Zhenan Bao,et al.  Biodegradable and flexible arterial-pulse sensor for the wireless monitoring of blood flow , 2019, Nature Biomedical Engineering.

[80]  Yi Li,et al.  A wearable potentiometric sensor with integrated salt bridge for sweat chloride measurement , 2017 .

[81]  Patricia Bet,et al.  Fall detection and fall risk assessment in older person using wearable sensors: A systematic review , 2019, Int. J. Medical Informatics.

[82]  Peyman F. Shahandashti,et al.  Highly conformable stretchable dry electrodes based on inexpensive flex substrate for long-term biopotential (EMG/ECG) monitoring , 2019, Sensors and Actuators A: Physical.

[83]  Min Zhang,et al.  Flexible, Stretchable Sensors for Wearable Health Monitoring: Sensing Mechanisms, Materials, Fabrication Strategies and Features , 2018, Sensors.

[84]  Yonggang Huang,et al.  Conformal piezoelectric systems for clinical and experimental characterization of soft tissue biomechanics. , 2015, Nature materials.

[85]  Joshua Ray Windmiller,et al.  Stamp transfer electrodes for electrochemical sensing on non-planar and oversized surfaces. , 2012, The Analyst.

[86]  Chris Van Hoof,et al.  Realization of a wearable miniaturized thermoelectric generator for human body applications , 2009 .

[87]  Kang Wang,et al.  1D/2D heterostructure nanofiber flexible sensing device with efficient gas detectivity , 2019, Applied Surface Science.

[88]  Nicholas D. Lane,et al.  From smart to deep: Robust activity recognition on smartwatches using deep learning , 2016, 2016 IEEE International Conference on Pervasive Computing and Communication Workshops (PerCom Workshops).

[89]  Sung-hoon Ahn,et al.  A flexible and highly sensitive strain-gauge sensor using reversible interlocking of nanofibres. , 2012, Nature materials.

[90]  Qing-Ming Wang,et al.  Carbon based polyimide nanocomposites thin film strain sensors fabricated by ink-jet printing method , 2019 .

[91]  Zhenan Bao,et al.  Wearable Bioelectronics: Opportunities for Chemistry. , 2019, Accounts of chemical research.

[92]  R. van Schaijk,et al.  Flexible Chloride Sensor for Sweat Analysis , 2015 .

[93]  Lili Wang,et al.  Ultrasensitive and ultraflexible e-skins with dual functionalities for wearable electronics , 2017 .

[94]  Yonggang Huang,et al.  Biaxially stretchable "wavy" silicon nanomembranes. , 2007, Nano letters.

[95]  Guanglei Li,et al.  Wearable biochemical sensors for human health monitoring: sensing materials and manufacturing technologies. , 2020, Journal of materials chemistry. B.

[96]  Shang Gao,et al.  Study on a paper-based piezoresistive sensor applied to monitoring human physiological signals , 2019, Sensors and Actuators A: Physical.

[97]  A. Pavic,et al.  Wearable inertial sensors to measure gait and posture characteristic differences in older adult fallers and non-fallers: A scoping review. , 2019, Gait & posture.

[98]  Xiaochen Dong,et al.  Recent progress of flexible and wearable strain sensors for human-motion monitoring , 2018 .

[99]  Xiaomin Ren,et al.  RGO-coated elastic fibres as wearable strain sensors for full-scale detection of human motions , 2017 .

[100]  Jin-Woo Park,et al.  Wearable transcutaneous oxygen sensor for health monitoring , 2019, Sensors and Actuators A: Physical.

[101]  J. Chae,et al.  Design and implementation of electrostatic micro-actuators in ultrasonic frequency on a flexible substrate, PEN (polyethylene naphthalate) , 2013 .

[102]  Ming Hu,et al.  Self-Powered Wearable Pressure Sensors with Enhanced Piezoelectric Properties of Aligned P(VDF-TrFE)/MWCNT Composites for Monitoring Human Physiological and Muscle Motion Signs , 2018, Nanomaterials.

[103]  Sanghun Jeon,et al.  Robust and scalable three-dimensional spacer textile pressure sensor for human motion detection , 2019, Smart Materials and Structures.

[104]  Shogo Nakata,et al.  A wearable pH sensor with high sensitivity based on a flexible charge-coupled device , 2018, Nature Electronics.

[105]  Tanja Schultz,et al.  Recognizing Hand and Finger Gestures with IMU based Motion and EMG based Muscle Activity Sensing , 2015, BIOSIGNALS.

[106]  Dipankar Mandal,et al.  Sustainable Energy Generation from Piezoelectric Biomaterial for Noninvasive Physiological Signal Monitoring , 2017 .

[107]  V. N. Nikitina,et al.  Nonenzymatic Sensor for Lactate Detection in Human Sweat. , 2017, Analytical chemistry.

[108]  Joseph Wang,et al.  Noninvasive Alcohol Monitoring Using a Wearable Tattoo-Based Iontophoretic-Biosensing System , 2016 .

[109]  Debes Bhattacharyya,et al.  Highly Stretchable Multifunctional Wearable Devices Based on Conductive Cotton and Wool Fabrics. , 2018, ACS applied materials & interfaces.

[110]  Michael C. McAlpine,et al.  Graphene-based wireless bacteria detection on tooth enamel , 2012, Nature Communications.

[111]  Shaowei Lu,et al.  Wearable graphene film strain sensors encapsulated with nylon fabric for human motion monitoring , 2019, Sensors and Actuators A: Physical.

[112]  Kun Dai,et al.  Highly Stretchable, Transparent, and Bio‐Friendly Strain Sensor Based on Self‐Recovery Ionic‐Covalent Hydrogels for Human Motion Monitoring , 2019, Macromolecular Materials and Engineering.

[113]  A. Caneschi,et al.  Temperature and pH sensors based on graphenic materials. , 2017, Biosensors & bioelectronics.

[114]  Hong Cheng-Yu,et al.  An FBG-based smart wearable ring fabricated using FDM for monitoring body joint motion , 2019, Journal of Industrial Textiles.

[115]  Tao Han,et al.  3D Printed Sensors for Biomedical Applications: A Review , 2019, Sensors.

[116]  Zhiming Zhang,et al.  From nanofibers to ordered ZnO/NiO heterojunction arrays for self-powered and transparent UV photodetectors , 2019, Journal of Materials Chemistry C.

[117]  Mohammad Reza Khosravani,et al.  3D-printed sensors: Current progress and future challenges , 2020, Sensors and Actuators A: Physical.

[118]  Huanyu Cheng,et al.  Biodegradable elastomers and silicon nanomembranes/nanoribbons for stretchable, transient electronics, and biosensors. , 2015, Nano letters.

[119]  V. P. Rachim,et al.  Wearable-band type visible-near infrared optical biosensor for non-invasive blood glucose monitoring , 2019, Sensors and Actuators B: Chemical.

[120]  Yong-Hoon Kim,et al.  Highly Sensitive Textile Strain Sensors and Wireless User-Interface Devices Using All-Polymeric Conducting Fibers. , 2017, ACS applied materials & interfaces.

[121]  Ning Wang,et al.  Patterned Metal/Polymer Strain Sensor with Good Flexibility, Mechanical Stability and Repeatability for Human Motion Detection , 2019, Micromachines.

[122]  L Tian,et al.  Wearable sensors: modalities, challenges, and prospects. , 2018, Lab on a chip.

[123]  Lee J. Hubble,et al.  Sensing at Your Fingertips: Glove‐based Wearable Chemical Sensors , 2018, Electroanalysis.

[124]  Yongzhe Zhang,et al.  High-performance temperature sensor based on silver nanowires , 2019, Materials Today Communications.

[125]  Sang‐Jae Kim,et al.  Adaptable piezoelectric hemispherical composite strips using a scalable groove technique for a self-powered muscle monitoring system. , 2018, Nanoscale.

[126]  Chunya Wang,et al.  An All-Silk-Derived Dual-Mode E-skin for Simultaneous Temperature-Pressure Detection. , 2017, ACS applied materials & interfaces.

[127]  Z. Çelik-Butler,et al.  Characterization and performance analysis of Li-doped ZnO nanowire as a nano-sensor and nano-energy harvesting element , 2018, Nano Energy.

[128]  Peng Fang,et al.  Flexible film-transducers based on polypropylene piezoelectrets: Fabrication, properties, and applications in wearable devices , 2017 .

[129]  Bin Sun,et al.  Wireless piezoelectric devices based on electrospun PVDF/BaTiO3 NW nanocomposite fibers for human motion monitoring. , 2018, Nanoscale.

[130]  Dario Floreano,et al.  Ultrastretchable Strain Sensors Using Carbon Black‐Filled Elastomer Composites and Comparison of Capacitive Versus Resistive Sensors , 2018 .

[131]  Jedrek Wosik,et al.  The Future of Wearables in Heart Failure Patients. , 2019, JACC. Heart failure.

[132]  Jung Woo Lee,et al.  Self-assembled three dimensional network designs for soft electronics , 2017, Nature Communications.

[133]  J. Sosnoff,et al.  Novel sensing technology in fall risk assessment in older adults: a systematic review , 2018, BMC Geriatrics.

[134]  Q. Fu,et al.  Highly Sensitive, Ultrastretchable Strain Sensors Prepared by Pumping Hybrid Fillers of Carbon Nanotubes/Cellulose Nanocrystal into Electrospun Polyurethane Membranes. , 2019, ACS applied materials & interfaces.

[135]  N. Gopalakrishnan,et al.  Printed flexible electrochemical pH sensors based on CuO nanorods , 2018, Sensors and Actuators B: Chemical.

[136]  Jia-Jia Li,et al.  Wearable Wide-Range Strain Sensors Based on Ionic Liquids and Monitoring of Human Activities , 2017, Sensors.

[137]  Raúl Aquino-Santos,et al.  WiSPH: A Wireless Sensor Network-Based Home Care Monitoring System , 2014, Sensors.

[138]  K. Hata,et al.  A stretchable carbon nanotube strain sensor for human-motion detection. , 2011, Nature nanotechnology.

[139]  Yichun Ding,et al.  Flexible and Compressible PEDOT:PSS@Melamine Conductive Sponge Prepared via One-Step Dip Coating as Piezoresistive Pressure Sensor for Human Motion Detection. , 2018, ACS applied materials & interfaces.

[140]  D. R. Chowdhury,et al.  Flexible metasurfaces and metamaterials: A review of materials and fabrication processes at micro- and nano-scales , 2015 .

[141]  Rossana E. Madrid,et al.  Potentiometric textile-based pH sensor , 2018 .

[142]  Xiaodong Chen,et al.  Healable, Transparent, Room-Temperature Electronic Sensors Based on Carbon Nanotube Network-Coated Polyelectrolyte Multilayers. , 2015, Small.

[143]  Halil Ceylan,et al.  Wearable Graphene Sensors With Microfluidic Liquid Metal Wiring for Structural Health Monitoring and Human Body Motion Sensing , 2016, IEEE Sensors Journal.

[144]  Abdulaziz A. Al Kheraif,et al.  Design and development of wireless wearable bio-tooth sensor for monitoring of tooth fracture and its bio metabolic components , 2020, Comput. Commun..

[145]  Inyeol Yun,et al.  Stretchable triboelectric multimodal tactile interface simultaneously recognizing various dynamic body motions , 2019, Nano Energy.

[146]  M. Kaltenbrunner,et al.  Ultraflexible organic photonic skin , 2016, Science Advances.

[147]  Kwang-Seok Yun,et al.  ECG Monitoring Garment Using Conductive Carbon Paste for Reduced Motion Artifacts , 2017, Polymers.

[148]  Yonggang Huang,et al.  Ultrathin conformal devices for precise and continuous thermal characterization of human skin. , 2013, Nature materials.

[149]  Meng Lu,et al.  Photonic crystal slab biosensors fabricated with helium ion lithography (HIL) , 2019, Sensors and Actuators A: Physical.

[150]  Kang Wang,et al.  Highly Active Co‐Based Catalyst in Nanofiber Matrix as Advanced Sensing Layer for High Selectivity of Flexible Sensing Device , 2018, Advanced Materials Technologies.

[151]  T. Arie,et al.  Wearable, Human‐Interactive, Health‐Monitoring, Wireless Devices Fabricated by Macroscale Printing Techniques , 2014 .

[152]  Quankang Wang,et al.  A Bioinspired Mineral Hydrogel as a Self‐Healable, Mechanically Adaptable Ionic Skin for Highly Sensitive Pressure Sensing , 2017, Advanced materials.

[153]  John A Rogers,et al.  Bio-Integrated Wearable Systems: A Comprehensive Review. , 2019, Chemical reviews.

[154]  Hongnian Yu,et al.  A survey on wearable sensor modality centred human activity recognition in health care , 2019, Expert Syst. Appl..

[155]  Chang Liu,et al.  Positive temperature coefficient thermistors based on carbon nanotube/polymer composites , 2014, Scientific Reports.

[156]  A. Javey,et al.  Roll-to-Roll Gravure Printed Electrochemical Sensors for Wearable and Medical Devices. , 2018, ACS nano.

[157]  Omid Kavehei,et al.  Transparent amorphous strontium titanate resistive memories with transient photo-response. , 2017, Nanoscale.

[158]  Nam-Joon Cho,et al.  Flexible, Graphene‐Coated Biocomposite for Highly Sensitive, Real‐Time Molecular Detection , 2016 .

[159]  H. Harry Asada,et al.  Artifact-resistant power-efficient design of finger-ring plethysmographic sensors , 2001, IEEE Transactions on Biomedical Engineering.

[160]  Yan Ma,et al.  Thermally Stable, Biocompatible, and Flexible Organic Field‐Effect Transistors and Their Application in Temperature Sensing Arrays for Artificial Skin , 2015 .

[161]  Yan Li,et al.  Stretchable and compressible piezoresistive sensors from auxetic foam and silver nanowire , 2019, Materials Chemistry and Physics.

[162]  Luke J. Currano,et al.  Wearable Sensor System for Detection of Lactate in Sweat , 2018, Scientific Reports.

[163]  Michele Caldara,et al.  Optical monitoring of sweat pH by a textile fabric wearable sensor based on covalently bonded litmus-3-glycidoxypropyltrimethoxysilane coating , 2016 .

[164]  Sang-Hoon Lee,et al.  CNT/PDMS Composite Flexible Dry Electrodesfor Long-Term ECG Monitoring , 2012, IEEE Transactions on Biomedical Engineering.

[165]  Kuo-Hui Yeh,et al.  A Secure IoT-Based Healthcare System With Body Sensor Networks , 2016, IEEE Access.

[166]  Joseph Wang,et al.  Epidermal tattoo potentiometric sodium sensors with wireless signal transduction for continuous non-invasive sweat monitoring. , 2014, Biosensors & bioelectronics.

[167]  Wendell K. T. Coltro,et al.  Wearable electrochemical sensors for forensic and clinical applications , 2019, TrAC Trends in Analytical Chemistry.

[168]  Hai Qiu,et al.  Application of Wearable Inertial Sensors and A New Test Battery for Distinguishing Retrospective Fallers from Non-fallers among Community-dwelling Older People , 2018, Scientific Reports.

[169]  Zamir Ahmed Abro,et al.  A novel flex sensor-based flexible smart garment for monitoring body postures , 2019, Journal of Industrial Textiles.

[170]  Yanlin Song,et al.  Inkjet printing wearable electronic devices , 2017 .