UC student Adam Hauke holds up the latest generation of sweat sensor in the Novel Devices Lab. (Credit: University of Cincinnati)

Researchers are developing cutting-edge biometric sensors that function without compromising the skin and its ability to prevent infection and dehydration. The new sensors generate sweat to glean biometric information.

The skin can provide misleading data to biosensors because it harbors bacteria and tends to collect salt and other minerals from dried sweat. An effective sensor has to bend and stretch like human skin, even as it adheres to the surface when the subject is moving. Electrical sensors that track your heartbeat have to account for noise both from within the body or the environment, such as from nearby electronics.

The researchers identifying innovative ways to glean information from human sweat. These devices are the size of a Band-Aid and are worn on the skin like one, too. The next generation of sweat-stimulating sensors generate sweat on a tiny patch of skin — even when the subject is resting and comfortable — and wick it away to sensors that measure substances like glucose. The biosensors collect and concentrate the faintest amounts of sweat into samples that sensors can read.

Among its other capabilities, the device measures the galvanic skin response, an indication of how much someone is sweating, he said.

The researchers note that biosensors of the future will measure multiple aspects of a person's physiology. And new wearable sensors will need a mix of disposable and reusable parts to address the wear and tear that come with daily life. They are also developing a new noninvasive technique to make sweat glands more permeable so sensors can record even more detailed data.