U.S. scientists create skin patch to measure sweat for health

Scientists in the United States have created a flexible skin patch that easily measures sweat levels while people exercise, and may help diagnose and monitor diseases in the future.

The skin patch, described in the journal Science Translational Medicine on Wednesday, is made of flexible material and is a little larger than a U.S. quarter.

People can stick the microfluidic device on their forearms or back like an adhesive bandage and start doing exercise. Tiny channels in the skin patch will collect perspiration and route it to four different reservoirs where it reacts with chemical reagents to produce color-based readings to reflect people's acidity level, concentrations of chloride, lactate and glucose.

Also, the measurements can indicate the wearer's hydration levels and electrolyte loss.

"Sweat is a rich, chemical broth containing a number of important chemical compounds with physiological health information," said John Rogers, a Northwestern University professor who led the research of what he called a "lab on the skin."

He explained that the device has integrated electronics that can connect wirelessly to a smartphone app, which analyzes the color-coded results.

That's one of its attractions, Rogers said. It allows people to monitor their health on the spot instead of waiting for the results of a blood test.

The skin patch, which is designed for one-time use of a few hours, can also detect a biomarker for cystic fibrosis.

Wednesday's study suggested that in the future, the device would be used in multiple ways to help diagnose disease or monitor health in people with chronic illnesses. Endi