A sweat-sensing skin patch that connects wirelessly with a smartphone may soon be able to track health during exercise and warn against dehydration. In a new study of 21 healthy volunteers, the soft and stretchable device successfully collected sweat and captured key markers, ranging from sweat rate to glucose and pH.

A soft, wearable microfluidic device for the capture, storage, and colorimetric sensing of sweat
Image Credit: J. Rogers, Northwestern University
Wearable technologies offer a new way of monitoring health and fitness. Sweat is an untapped, yet rich source of biomarkers - including electrolytes, small molecules, and proteins - that could potentially be used to diagnose diseases like cystic fibrosis.