Jin Zhang, a professor at the University of Western Ontario, is developing contact lenses that change color with the user's blood sugar level. This could allow diabetics to monitor themselves without frequent blood samples. The technology:
http://www.nano.org.uk/news/index.php?article=319 via io9 | Image: NASA
...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 colour.
http://www.nano.org.uk/news/index.php?article=319 via io9 | Image: NASA
I see what you did there.
BTW - that article you linked to was really poorly written. (But scientists just have to do good science, right, not necessarily communicate it.)