Scientists from the University of California, San Diego, have unveiled an innovative device - a “smart” armband. It provides continuous health monitoring using sweat as a source of energy. The wristband fits snugly on the finger and uses natural sweat to generate electricity. Special bioelectric cells located in the skin contact area convert the chemicals in the sweat into electricity. The resulting energy is stored in stretchable batteries and powers sensors that measure indicators such as glucose levels, vitamin C, lactate and levodopa. The development transmits data via Bluetooth to a special app, allowing users to continuously monitor their health even while resting or sleeping. In the future, the researchers want to refine the device and create a closed-loop system that can not only track health indicators, but also prescribe treatment based on the collected data.