Article
Engineering, Biomedical
Xue Wang, Xiao Xiao, Zhiping Feng, Yufen Wu, Jin Yang, Jun Chen
Summary: A soft bioelectronic patch has been developed to monitor respiration and cardiovascular activities during sleep in a wearable and non-invasive manner. The patch exhibits high sensitivity and low-frequency response, making it suitable for sleep monitoring and diagnosis of obstructive sleep apnea-hypopnea syndrome.
ADVANCED HEALTHCARE MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Mingyu Sang, Kyubeen Kim, Jongwoon Shin, Ki Jun Yu
Summary: This study introduces the recent developments in wearable and implantable bioelectronics through the use of ultra-thin encapsulation technologies and novel materials, aiming to improve the stability and electrical performance of the devices and optimize their use in physiological environments.
Article
Chemistry, Physical
Yuanjie Su, Weixiong Li, Liu Yuan, Chunxu Chen, Hong Pan, Guangzhong Xie, Giorgio Conta, Susanna Ferrier, Xun Zhao, Guorui Chen, Huiling Tai, Yadong Jiang, Jun Chen
Summary: The study focused on doping ceramic nanofillers into polymer matrices to develop high-performance nanocomposites, with the goal of enhancing the interaction between the nanofillers and polymer matrix. Through experimental and theoretical analysis, it was found that polydopamine (PDA) coating on the ceramic nanoparticles could effectively promote the interaction, leading to improved composite performance. Based on this finding, a polydopamine modified nonwoven piezoelectric textile was successfully constructed, demonstrating outstanding sensitivity and long-term stability for wearable biomonitoring applications.
Article
Chemistry, Multidisciplinary
Keyu Meng, Xiao Xiao, Zixiao Liu, Sophia Shen, Trinny Tat, Zihan Wang, Chengyue Lu, Wenbo Ding, Ximin He, Jun Yang, Jun Chen
Summary: A highly sensitive and conformal pressure sensor inspired by kirigami structure is developed to accurately monitor human pulse wave. The sensor demonstrates superior sensitivity and stability under various conditions, and a wireless monitoring system is developed to transmit pulse signals in real-time to a mobile phone, successfully distinguishing pulse waveforms from different participants, equivalent to results from commercial medical devices.
ADVANCED MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Zhiyuan Gao, Xiao Xiao, Aiden Di Carlo, Junyi Yin, Yanxin Wang, Linjun Huang, Jianguo Tang, Jun Chen
Summary: Wearable strain sensors based on electrospun fibers have gained popularity in personalized healthcare due to their excellent mechanical properties, breathability, and light weight. This review provides a systematic introduction to the structure and preparation process of electrospun fibers and the conductive layer. It also discusses the impact of materials and structures on the sensing performance of wearable strain sensors and presents applications in biomonitoring, motion detection, and human-machine interaction. Challenges and future directions for the community of wearable strain sensors based on electrospun fibers are also highlighted.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Review
Engineering, Biomedical
Young-Geun Park, Ga-Yeon Lee, Jiuk Jang, Su Min Yun, Enji Kim, Jang-Ung Park
Summary: Liquid metals, known for their excellent stretchability and biocompatibility, are being extensively explored as conductors for wearable healthcare devices, providing crucial support for personal health management.
ADVANCED HEALTHCARE MATERIALS
(2021)
Review
Engineering, Biomedical
Hyung Joon Shim, Sung-Hyuk Sunwoo, Yeongjun Kim, Ja Hoon Koo, Dae-Hyeong Kim
Summary: This article reviews recent progress in the functionalization of elastomers and their application in intrinsically soft and biointegrated electronics, including adding fillers for functionalization, synthesizing or processing conducting or semiconducting elastomers, and employing other functionalization strategies to improve device performance.
ADVANCED HEALTHCARE MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Jianren Huang, Anbang Chen, Songjiu Han, Qirui Wu, Jundong Zhu, Jiayu Zhang, Yujia Chen, Jiantao Liu, Lunhui Guan
Summary: Soft strain gauges offer a flexible and versatile alternative to traditional gauges, with improved fracture energy, fatigue threshold, and sensing performance. A mechanically interlocked gel-elastomer hybrid material is utilized for the strain gauge, providing exceptional strength and stretchability. The resulting electrode demonstrates excellent detection capabilities for human-related vibrations, enabling the measurement of physiological parameters and the development of an intelligent motion detection system.
Article
Nanoscience & Nanotechnology
Qichao Li, Yamin Liu, Di Chen, Jianmin Miao, Chunlei Zhang, Daxiang Cui
Summary: In this study, wearable strain sensors with good sensitivity, stretchability, softness, durability, and biocompatibility were prepared using soft silicone elastomer and carbon nanotubes. The sensors exhibited high sensitivity and a large sensing strain range, as well as strong robustness and biocompatibility.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Yong Long, Zhuo Wang, Fan Xu, Bin Jiang, Junfeng Xiao, Jun Yang, Zhong Lin Wang, Weiguo Hu
Summary: A triple-network conductive hydrogel has been developed by combining 2D Ti3C2Tx nanosheets with two types of polymer chains. The hydrogel exhibits mechanical robustness, super elasticity, and excellent fatigue resistance, making it suitable for wearable electronics and strain/pressure sensors.
Article
Chemistry, Multidisciplinary
Shuwen Chen, Shicheng Fan, Jiaming Qi, Ze Xiong, Zheng Qiao, Zixiong Wu, Joo Chuan Yeo, Chwee Teck Lim
Summary: A bilayer liquid-solid conductor (b-LSC) with amphiphilic properties is introduced in this study to interface reliably with both rigid electronics and elastomeric substrates. It exhibits high strain-insensitive conductivity, extreme stretchability, and negligible resistance change under ultra-high strain. The b-LSC can be used for various applications, such as stretchable sensor arrays, multi-layered stretchable displays, and highly integrated haptic user-interactive optoelectric E-skins.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yehu David Horev, Arnab Maity, Youbin Zheng, Yana Milyutin, Muhammad Khatib, Miaomiao Yuan, Ran Yosef Suckeveriene, Ning Tang, Weiwei Wu, Hossam Haick
Summary: A highly gas-permeable ultra-thin strain sensor has been developed by covalently grafting nanofibrous polyaniline (PANI) onto stretchable elastomer nanomeshes, demonstrating low weight, intimate connection with skin, stable performance, and continuous recording of complex movements.
ADVANCED MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Yaqing Feng, Xiangyu Chen, Qingxun Wu, Guofeng Cao, David McCoul, Bo Huang, Jianwen Zhao
Summary: Compared to rigid sensors, soft stain sensors are more suitable for measuring human joint motion due to their comfort. A quick and automatic self-calibration method for soft strain sensors has been proposed in this paper, resulting in small measurement errors and feasibility in engineering applications.
IEEE SENSORS JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Guorui Chen, Yihao Zhou, Yunsheng Fang, Xun Zhao, Sophia Shen, Trinny Tat, Ardo Nashalian, Jun Chen
Summary: The study demonstrates the giant magnetoelastic effect in soft elastomer systems without the need for external magnetic fields, with a higher magnetomechanical coupling factor compared to traditional metal-based ferromagnetic materials. By combining this effect with electromagnetic induction, a wearable MEG was developed for biomechanical energy conversion, showcasing high output current, low internal impedance, and waterproof properties. The wearable MEG was also utilized as a power source for personalized thermoregulation, showing an increase in temperature in the fiber-shaped resistor.
Article
Chemistry, Applied
Namsun Chou, Hyunmin Moon, Jinhee Park, Sohee Kim
Summary: The study focused on the microcracks in Parylene C-filled PDMS substrates, analyzing the phenomenon by quantifying the penetration depth, the amount of Parylene C on the surface and in the interfacial region. It was found that only etching the Parylene C from the PDMS surface was the optimal condition for fabricating the filled PDMS substrate.
PROGRESS IN ORGANIC COATINGS
(2021)
Article
Biochemical Research Methods
Kyle E. Parker, Juhyun Lee, Jenny R. Kim, Chinatsu Kawakami, Choong Yeon Kim, Raza Qazi, Kyung-In Jang, Jae-Woong Jeong, Jordan G. McCall
Summary: This article describes a low-cost production method for customizable optical neural probes using a 3D printer, allowing for the control of neural circuit activity in live animals. The method eliminates the need for expensive materials and specialized facilities, and offers quick customization for experimental needs, improving the flexibility of optogenetic experimental design.
Article
Nanoscience & Nanotechnology
Sehyun Park, Seunghyeb Ban, Nathan Zavanelli, Andrew E. Bunn, Shinjae Kwon, Hyo-ryoung Lim, Woon-Hong Yeo, Jong-Hoon Kim
Summary: Recent advances in soft materials and nano-microfabrication have made it possible to develop flexible wearable electronics. Printing technologies have shown efficiency and compatibility with polymeric materials for manufacturing wearable electronics. In this study, fully screen-printable, skin-conformal electrodes were presented for low-cost and scalable manufacturing of wearable electronics. The screen printing process enables easy, cost-effective, and high-throughput manufacturing, while the ink used for the conductive layer printing allows for natural deformation under stretching and bending conditions. Real-time wireless electrocardiogram monitoring was successfully demonstrated using the printed electrodes, with an algorithm developed for accurate heart rate and respiratory rate calculations, as well as arrhythmia detection.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Uijung Yong, Donghwan Kim, Hojoong Kim, Dong Gyu Hwang, Sungkeon Cho, Hyoryung Nam, Sejin Kim, Taeyeong Kim, Unyong Jeong, Keehoon Kim, Wan Kyun Chung, Woon-Hong Yeo, Jinah Jang
Summary: Drug-induced cardiotoxicity is a major challenge in early-stage drug development due to the lack of a physiologically relevant preclinical cardiotoxicity test. A biohybrid 3D printing technology is introduced to fabricate a tissue-sensor platform for continuous monitoring of acute and chronic drug effects. The platform combines a strain gauge sensor and engineered heart tissue (EHT), enabling the observation of EHT contractile force and potential drug cardiotoxicity.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Subin Oh, Sunwoo Lee, Sang-Hyuk Byun, Simok Lee, Choong Yeon Kim, Junwoo Yea, Sein Chung, Shuo Li, Kyung-In Jang, Jiheong Kang, Jae-Woong Jeong
Summary: This study presents a versatile shape-morphing display that can reconfigure its shape into various complex 3D structures through electrothermal operation and maintain its morphed states without power consumption. The experimental studies and proof-of-concept demonstrations show the potential of this shape-morphing display in 3D art displays, transformative wearable electronics, and visio-tactile automotive interfaces.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Analytical
Yongkuk Lee, Suresh Pokharel, Asra Al Muslim, Dukka B. Kc, Kyoung Hag Lee, Woon-Hong Yeo
Summary: Older adults are more prone to falling due to normal aging changes, posing serious medical risks and incurring high healthcare and societal costs. However, there is a lack of automatic fall detection systems specifically designed for older adults. This paper introduces a wireless and flexible skin-wearable electronic device for accurate motion sensing and user comfort, along with a deep learning-based algorithm for reliable fall detection in older adults.
Article
Chemistry, Multidisciplinary
Ju Young Lee, Jongwoon Shin, Kyubeen Kim, Jeong Eun Ju, Ankan Dutta, Tae Soo Kim, Young Uk Cho, Taemin Kim, Luhing Hu, Won Kyung Min, Hyun-Suh Jung, Young Sun Park, Sang Min Won, Woon-Hong Yeo, Jooho Moon, Dahl-Young Khang, Hyun Jae Kim, Jong-Hyun Ahn, Huanyu Cheng, Ki Jun Yu, John A. Rogers
Summary: Ultrathin crystalline silicon is widely used in high-performance, flexible, and stretchable electronics due to its excellent properties, but its fabrication process is expensive and complicated. In this study, a simple transfer method is proposed to print ultrathin crystalline silicon sheets with various thicknesses from a single mother wafer, achieving high areal density. The electronic applications of these silicon membranes, such as flexible solar cells and transistor arrays, are successfully demonstrated.
Review
Nanoscience & Nanotechnology
Hodam Kim, Yoon Jae Lee, Garan Byun, Chanyoung Choi, Woon-Hong Yeo
Summary: Recent advances in soft sensors and flexible electronics have enabled various applications in detecting physical, electrical, and chemical signals. However, there are still technical barriers in terms of mechanical, electrical, and material properties that hinder enhanced signal sensing. This review summarizes the latest advancements in materials, manufacturing, and integration technologies for developing ultrathin soft sensors to monitor human physiological signals. Improving the soft and compliant structures and mechanical properties is crucial for creating reliable wearable electronic systems. The article also discusses the limitations and current trends in developing multifunctional sensors, self-powered devices, and integration with external stimuli systems.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Biomedical
Hojoong Kim, Young Jin Yoo, Joo Ho Yun, Se-Yeon Heo, Young Min Song, Woon-Hong Yeo
Summary: Researchers have developed a soft, wearable bioelectronic system for detecting outdoor workers' stress levels. The system integrates nanofabric radiative cooler and miniaturized sensors to measure stable electrodermal activities and temperature in hot outdoor conditions, enabling continuous health monitoring.
ADVANCED HEALTHCARE MATERIALS
(2023)
Article
Automation & Control Systems
Seunghyeb Ban, Yoon Jae Lee, Ki Jun Yu, Jae Won Chang, Jong-Hoon Kim, Woon-Hong Yeo
Summary: This study introduces a two-camera eye-tracking system and a data classification method for human-machine interfaces (HMIs). The system uses machine-learning technology to accurately control a robotic arm by continuously classifying gaze and eye directions in real time. The results show that the deep-learning classification algorithm achieves exceptional accuracy (99.99%) with a high number of actions per command (>= 64), outperforming other HMI systems.
ADVANCED INTELLIGENT SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Seunghyeb Ban, Yoon Jae Lee, Shinjae Kwon, Yun-Soung Kim, Jae Won Chang, Jong-Hoon Kim, Woon-Hong Yeo
Summary: Recent advances in wearable technologies have enabled eye movement-enabled human-machine interfaces (HMIs) using electrooculography (EOG) measured by dry electrodes. A low-profile, headband-type soft wearable electronic system with embedded stretchable electrodes and a flexible wireless circuit was developed for continuous HMIs. Real-time classification of eye motions achieved 98.3% accuracy with a convolutional neural network, showcasing the high performance of the bioelectronic system and algorithm for various HMI and VR applications.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Jihoon Kim, Prakyath Kantharaju, Hoon Yi, Michael Jacobson, Hyungkeun Jeong, Hojoong Kim, Jinwoo Lee, Jared Matthews, Nathan Zavanelli, Hyeonseok Kim, Heejin Jeong, Myunghee Kim, Woon-Hong Yeo
Summary: This paper reports a soft, flexible bioelectronic system that integrates a wearable ankle-foot exoskeleton, used to estimate metabolic costs and physical effort, demonstrating the potential for real-time wearable robot adjustments based on biofeedback.
NPJ FLEXIBLE ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Hodam Kim, Ho-Seung Cha, Minseon Kim, Yoon Jae Lee, Hoon Yi, Sung Hoon Lee, Soltis Ira, Hojoong Kim, Chang-Hwan Im, Woon-Hong Yeo
Summary: Augmented reality (AR) is a computer graphics technique that seamlessly connects the real and virtual worlds. This paper introduces an AR-integrated soft wearable electronic system that detects hand gestures for intuitive and accurate control of external systems.
Article
Biophysics
Bruno Rigo, Allison Bateman, Jimin Lee, Hyeonseok Kim, Yunki Lee, Lissette Romero, Young C. Jang, Robert Herbert, Woon-Hong Yeo
Summary: Atherosclerosis is a major cause of cardiovascular diseases, and in-stent restenosis is a common complication of angioplasty. This study presents an implantable vascular bioelectronic device with a miniaturized strain sensor, fabricated using microneedle printing methods. The sensor is integrated with a wireless vascular stent, allowing real-time monitoring of restenosis progression. The system shows potential for monitoring various cardiovascular diseases and stent-integrated sensing/treatments.
BIOSENSORS & BIOELECTRONICS
(2023)
Review
Chemistry, Analytical
Jared Matthews, Jihoon Kim, Woon-Hong Yeo
Summary: Wearable devices have the ability to noninvasively monitor physiological signals, and machine learning techniques can be used to process and analyze these signals, filling gaps in conventional clinical practice and providing cost-effective health monitoring.
ANALYSIS & SENSING
(2023)