Scientists have developed a graphene-based patch that can monitor the blood glucose levels of diabetics without piercing the skin. Unlike the conventional finger-prick blood tests that diabetics use on a daily basis, this device utilizes a small electric current to draw glucose from under the skin. The extracted glucose is then collected in tiny reservoirs, where it’s measured every 10 to 15 minutes. It is hoped that, once commercialized, the inexpensive disposable device could wirelessly transmit those readings to an app on the user’s smartphone, providing alerts when necessary.