A researcher in Baltimore has created a contact lens that can offer diabetic patients a non-invasive technique of monitoring their blood sugar level.
Dr. Chris Geddes of the University of Maryland Biotechnology Institute has developed contact lenses that change color in response to the glucose level in the wearer’s tears, KENS-TV in San Antonio reports.
Tears have a tiny concentration of glucose, about 1-10th of that of blood and there’s a lag time of about 15 minutes before the eye registers the level.
Geddes said, “We’ve developed very special molecules that sense glucose at very low levels. We’ve incorporated these inside commercially available contact lenses. The test is completely non-invasive and it’s continuous.”
“And that color can be easily determined against a pre-calibrated test strip that one would hold up and look at, and you can determine your own glucose levels,” Geddes said.
In other words, a person wearing the glucose-sensitive lenses would see a small translucent dot on the left side of the visual field. That dot would change color, warning the patient of dangerously low or high blood sugar levels.
Developing this technology has taken many years. Further testing is essential before the lenses hit stores. The scientists are eagerly seeking a commercial partner so they can start testing the lenses in animals and people.
Experts in Baltimore are also working on contact lenses to sense cholesterol levels and lenses soldiers could wear for early detection of attacks with weapons like anthrax and cyanide.