Contact lenses change color when blood glucose increases in diabetics

In the future, diabetics may be able to wear contact lenses that continuously alert them to variations in their glucose levels by changing colors - potentially replacing the need to routinely draw blood throughout the day.

The non-invasive technology, developed by Chemical and Biochemical Engineering professor Jin Zhang at The University of Western Ontario, uses extremely small nanoparticles embedded into the hydrogel lenses. These engineered nanoparticles react with glucose molecules found in tears, causing a chemical reaction that changes their color.

References:
Nanocomposites could change diabetes treatment. The University of Western Ontario, 2010.

Image source: OpenClipArt.org.