You stick the patch on your skin when you start moving and tiny channels collect your sweat and route it to different compartments where it interacts with chemicals that change color to reflect sweat loss, the acidity level of perspiration, and concentrations of chloride, glucose, and lactate. To get the data, a user takes a smartphone photo of the device. An app then analyzes that photo and displays the information.
The device is disposable, designed to be used once for a few hours while attached to the skin of the forearm or back. “Sweat has biochemical components within it that tell us a lot about physiological health,” said Rogers.
Why bother analyzing sweat?
Rogers said in a university news release, it’s “a rich, chemical broth containing a number of important chemical compounds with physiological health information.” Researchers tested the device on two groups of cyclists and reported their findings in the journal Science Translational Medicine. They said the device gave accurate accounts of the acidity of sweat and concentrations of glucose, chloride, and lactate.
The patches stayed in place and worked even when people wore them in an outdoor race. The sweat patches are designed for a one-time use over a couple of hours.