Contact lenses check blood sugar

BALTIMORE, Nov. 13 (UPI) -- A scientist in Baltimore has developed a contact lens that can provide diabetics with a non-invasive way to monitor blood sugar.

Instead of using blood, Dr. Chris Geddes of the University of Maryland Biotechnology Institute has produced 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.

"We've developed very special molecules that sense glucose at very low levels," said Geddes. "We've incorporated these inside commercially available contact lenses. The test is completely non-invasive and it's continuous."

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.

Before the lenses can be commercially available, further testing is needed.

The Baltimore scientists are also working on contact lenses that sense cholesterol levels.

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