Imagine being able to measure your blood sugar levels, know if you’ve had too much to drink, and track your muscle fatigue during a workout, all in one small device worn on your skin. Engineers at the University of California San Diego have developed a prototype of such a wearable that can continuously monitor several health stats—glucose, alcohol, and lactate levels—simultaneously in real-time.
The device is about the size of a stack of six quarters. It is applied to the skin through a Velcro-like patch of microscopic needles, or microneedles, that are each about one-fifth the width of a human hair. Wearing the device is not painful—the microneedles barely penetrate the surface of the skin to sense biomolecules in interstitial fluid, which is the fluid surrounding the cells beneath the skin. The device can be worn on the upper arm and sends data wirelessly to a custom smartphone app.
Researchers at the UC San Diego Center for Wearable Sensors describe their device in a paper published May 9 in Nature Biomedical Engineering.