TY - JOUR
T1 - Wireless, soft electronics for rapid, multisensor measurements of hydration levels in healthy and diseased skin
AU - Kwon, Kyeongha
AU - Wang, Heling
AU - Lim, Jaeman
AU - Chun, Keum San
AU - Jang, Hokyung
AU - Yoo, Injae
AU - Wu, Derek
AU - Chen, Alyssa Jie
AU - Gu, Carol Ge
AU - Lipschultz, Lindsay
AU - Kim, Jong Uk
AU - Kim, Jihye
AU - Jeong, Hyoyoung
AU - Luan, Haiwen
AU - Park, Yoonseok
AU - Su, Chun Ju
AU - Ishida, Yui
AU - Madhvapathy, Surabhi R.
AU - Ikoma, Akihiko
AU - Kwak, Jean Won
AU - Yang, Da Som
AU - Banks, Anthony
AU - Xu, Shuai
AU - Huang, Yonggang
AU - Chang, Jan Kai
AU - Rogers, John A.
N1 - Publisher Copyright:
© 2021 National Academy of Sciences. All rights reserved.
PY - 2021/2/2
Y1 - 2021/2/2
N2 - Precise, quantitative measurements of the hydration status of skin can yield important insights into dermatological health and skin structure and function, with additional relevance to essential processes of thermoregulation and other features of basic physiology. Existing tools for determining skin water content exploit surrogate electrical assessments performed with bulky, rigid, and expensive instruments that are difficult to use in a repeatable manner. Recent alternatives exploit thermal measurements using soft wireless devices that adhere gently and noninvasively to the surface of the skin, but with limited operating range (∼1 cm) and high sensitivity to subtle environmental fluctuations. This paper introduces a set of ideas and technologies that overcome these drawbacks to enable high-speed, robust, long-range automated measurements of thermal transport properties via a miniaturized, multisensor module controlled by a long-range (∼10 m) Bluetooth Low Energy system on a chip, with a graphical user interface to standard smartphones. Soft contact to the surface of the skin, with almost zero user burden, yields recordings that can be quantitatively connected to hydration levels of both the epidermis and dermis, using computational modeling techniques, with high levels of repeatability and insensitivity to ambient fluctuations in temperature. Systematic studies of polymers in layered configurations similar to those of human skin, of porcine skin with known levels of hydration, and of human subjects with benchmarks against clinical devices validate the measurement approach and associated sensor hardware. The results support capabilities in characterizing skin barrier function, assessing severity of skin diseases, and evaluating cosmetic and medication efficacy, for use in the clinic or in the home.
AB - Precise, quantitative measurements of the hydration status of skin can yield important insights into dermatological health and skin structure and function, with additional relevance to essential processes of thermoregulation and other features of basic physiology. Existing tools for determining skin water content exploit surrogate electrical assessments performed with bulky, rigid, and expensive instruments that are difficult to use in a repeatable manner. Recent alternatives exploit thermal measurements using soft wireless devices that adhere gently and noninvasively to the surface of the skin, but with limited operating range (∼1 cm) and high sensitivity to subtle environmental fluctuations. This paper introduces a set of ideas and technologies that overcome these drawbacks to enable high-speed, robust, long-range automated measurements of thermal transport properties via a miniaturized, multisensor module controlled by a long-range (∼10 m) Bluetooth Low Energy system on a chip, with a graphical user interface to standard smartphones. Soft contact to the surface of the skin, with almost zero user burden, yields recordings that can be quantitatively connected to hydration levels of both the epidermis and dermis, using computational modeling techniques, with high levels of repeatability and insensitivity to ambient fluctuations in temperature. Systematic studies of polymers in layered configurations similar to those of human skin, of porcine skin with known levels of hydration, and of human subjects with benchmarks against clinical devices validate the measurement approach and associated sensor hardware. The results support capabilities in characterizing skin barrier function, assessing severity of skin diseases, and evaluating cosmetic and medication efficacy, for use in the clinic or in the home.
KW - Biomedical devices
KW - Diagnostics
KW - Flexible electronics
KW - Health monitoring
KW - Wireless electronics
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U2 - 10.1073/pnas.2020398118
DO - 10.1073/pnas.2020398118
M3 - Article
C2 - 33468630
AN - SCOPUS:85100015794
SN - 0027-8424
VL - 118
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 5
M1 - e2020398118
ER -