Multimodal epidermal devices for hydration monitoring

A new type of sensor that is practically imperceptible to the wearer could help to track changes in skin hydration. A team in the United States, led by John Rogers at Northwestern University, Illinois, and Rafal Pielak from the L’Oreal Tech Incubator, California, fabricated small patches that can read both thermal and electrical properties of the skin. Studies with porcine skin and computational models enabled the researchers to determine how to collect such measurements and turn them into a useful metric of skin hydration. The team then tested the device on 20 people treated with creams containing varying levels of glycerin, a skin moisturizer. The sensor performed just as well as existing technologies but was also more convenient to use. It could help companies to test skin products or enable at-home skin monitoring.