The New Scientist reports that researchers at the University of Maryland have developed contact lenses that change their appearance according to the wearer's blood sugar level.
"To make glucose-sensing contacts, scientists added boronic acid to disposable contact lenses. Moisture from the tear ducts contains glucose that binds with the molecules of boronic acid, with the reaction causing fluorescence. A handheld device flashes a blue light into the eye and measures the intensity of the resulting glow, letting the user know their blood glucose level."
Lead author of the study Chris Geddes and his team at the Center for Fluroscence Spectroscopy are also working on lenses that would be able to monitor levels of sodium, potassium, and cholesterol. The full article can be found in this month's Current Opinion in Biotechnology.