Future diabetes patients won’t have to stick themselves with a needle; they’ll just need to get a tattoo. Researchers have developed a temporary paper-based tattoo that applies a mild electrical shock to the skin to measure blood glucose levels. In a study of seven individuals—four males and three females—who wore the tattoo while eating a carbohydrate-rich meal in the lab, the device (pictured) was just as effective at measuring glucose levels as the traditional method, the finger stick monitor. None of the volunteers reported any discomfort during the tests, the team reports in the current issue of Analytical Chemistry, although some of them did point out a tingling feeling when the tattoo was taking its measurements. The device does not currently provide a numerical reading that diabetes patients would need to monitor their condition, but this is in the cards. Other possible applications include sending the information to the patient’s doctor in real time using Bluetooth. Now, the tattoo works for a whole day; the researchers are working on making the tattoo last longer while keeping it at its current cost of a few cents.