May 5, 2024

No Sweat: Superhydrophobic Biosensor Reads Your Body’s Invisible Signals

Memorial Associate Professor of Engineering Science and Mechanics, features superhydrophobic product that determines sweat vapor without soaking up water. Not all sweat is created equal, and some can not be determined with current sensing units. Wearable sensors can offer constant, non-invasive tracking of this type of sweat. Cheng developed a model of a superhydrophobic sweat sensing unit to measure vapor from insensible sweating. The product– a superabsorbent hydrogel composite on a porous substrate sandwiched in between 2 superhydrophobic textile layers– permits the permeation of sweat vapor while avoiding the sensing unit from being affected by the external water beads of sensible perspiration.

A biosensor established by Huanyu “Larry” Cheng, the James L. Henderson, Jr. Memorial Associate Professor of Engineering Science and Mechanics, features superhydrophobic product that measures sweat vapor without taking in water. Credit: Provided by Larry Cheng/Penn State
A brand-new superhydrophobic biosensor enables the tracking of “insensible” sweat (vaporized water loss from the skin), which was previously hard to determine. This sensor can be integrated into wearable tech for continuous tracking, aiding in assessing body thermoregulation, skin health, illness conditions, nervous system activity, and detection of other health biomarkers.
Not all sweat is developed equal, and some can not be measured with existing sensors. A recently established superhydrophobic biosensor could be utilized as a diagnostic tool to identify such types of sweat.
The sensor, developed by Huanyu “Larry” Cheng, James L. Henderson, Jr. Memorial Associate Professor of Engineering Science and Mechanics, was included in a paper released in the journal ACS Nano.

Practical, or liquid, sweating is sweat that can be perceived by a person, such as throughout extensive exercise. Wearable sensing units can supply constant, non-invasive tracking of this type of sweat.
” Monitoring insensible sweat is of high interest for evaluating skin health and illness conditions, such as eczema and wound healing, in addition to underlying health statuses, such as discomfort or stress and anxiety,” Cheng stated. “Skin-interfaced gadgets that identify sweat rate and loss are currently restricted to dealing with sensible sweat and are not ideal for insensible sweat in a vapor state.”
A superabsorbent hydrogel composite on a porous substrate is sandwiched between 2 superhydrophobic fabric layers to permit the permeation of sweat vapor while avoiding the sensing unit from being affected by the external water droplets of practical perspiration. Credit: Provided by Larry Cheng/Penn State
Cheng developed a model of a superhydrophobic sweat sensing unit to measure vapor from insensible sweating. The product– a superabsorbent hydrogel composite on a porous substrate sandwiched in between 2 superhydrophobic fabric layers– permits the permeation of sweat vapor while avoiding the sensing unit from being affected by the external water droplets of practical perspiration. The sensing unit could be incorporated with a flexible cordless communication and powering module that continually monitors sweat rates at different body locations.
” Proof-of-concept demonstrations on human topics showcased the feasibility to continually evaluate the bodys thermoregulation and skin barrier functions,” Cheng said. “This makes it possible for the assessment of thermal convenience, disease conditions and nerve system activity and supplies a low-cost gadget platform to identify other health-relevant biomarkers in the sweat vapor as the next-generation sweat sensor for wise healthcare and personalized medication.”
Reference: “Skin-Interfaced Superhydrophobic Insensible Sweat Sensors for Evaluating Body Thermoregulation and Skin Barrier Functions” by Yangchengyi Liu, Xiaofeng Li, Hanlin Yang, Ping Zhang, Peihe Wang, Yi Sun, Fengzhen Yang, Weiyi Liu, Yujing Li, Yao Tian, Shun Qian, Shangda Chen, Huanyu Cheng and Xiufeng Wang, 6 February 2023, ACS Nano.DOI: 10.1021/ acsnano.2 c11267.
Chengs work was supported in part by the National Institutes of Health, the National Science Foundation and Penn State. The National Natural Science Foundation of China, the Natural Science Foundation of Hunan Province and the Furong Scholars of Hunan Province program also offered support.
Co-authors consist of Shangda Chen, Xiaofeng Li, Yujing Li, Weiyi Liu, Yangchengyi Liu, Shun Qian, Yi Sun, Yao Tian, Peihe Wang, Xiufeng Wang, Fengzhen Yang, Hanlin Yang and Ping Zhang, all affiliated with Xiangtan University in China.