Unlike commercially available hydration monitors that are expensive and bulky, researchers from North Carolina State University have now developed a cost-effective wearable wireless sensor to monitor a person’s skin hydration in real time, allowing detection of dehydration before it culminates into a health issue.
The sensor is lightweight, flexible and stretchable, and has already been incorporated into prototype devices that can be worn on the wrist or as a chest patch. It wirelessly transmits data to a program that can be run on a laptop, tablet or smartphone, allowing data monitoring by the user or a designated third party such as a doctor in a hospital setting or an officer in a military setting.
The sensor comprises of two elastic polymer composite electrodes containing conductive silver nano-wires. In order to detect the hydration level of the skin, these electrodes monitor the skin’s electrical properties that change predictably based on an individual’s hydration.
Lab tests conducted on custom-made artificial skins over a broad range of hydration levels indicated that the sensor’s performance was not affected by ambient humidity, and its accuracy matched commercial hydration monitors that are based on similar principles but employ rigid probes.
The research paper titled “A Wearable Hydration Monitor with Conformal Nanowire Electrodes” has been published in the journal Advanced Healthcare Materials. It is co-authored by NC Ph.D. students Amanda Myers and Abhishek Malhotra, Feiyan Lin (former NC graduate) and NC Associate Professor of Electrical and Computer Engineering Alper Bozkurt.
According to John Muth, an NC professor of electrical engineering and co-corresponding author, measuring a person’s hydration level quantitatively is difficult but relevant for people such as military personnel, athletes and firefighters who are at a risk of heat stress and associated health problems when training or in the field.
“We have developed technology that allows us to track an individual’s skin hydration in real time,” says Yong Zhu, associate professor of mechanical and aerospace engineering at NC State and co-corresponding author. “Our sensor could be used to protect the health of people working in hot conditions, improve athletic performance and safety, and track hydration in older adults or in medical patients suffering from various conditions. It can even be used to tell how effective skin moisturizers are for cosmetics.”
“Commercially available monitors we tested our system against costs more than $8,000,” says Shanshan Yao, a Ph.D. student at NC State and lead author of the paper. “Our sensor costs about one dollar, and the overall manufacturing cost of the wearable systems we developed would be no more than a common wearable device such as a Fitbit.”
More information can be found at: North Carolina State University.