Diabetes Health Center

Glucose Meters: What's on the Horizon?

See It in Your Eyes

Like the 1970s mood rings, your contact lenses could someday reflect your glucose level. With one glance in a mirror, you'll see whether you're headed for trouble.

This eye-opening innovation has been a 20-year-long project headed by Sanford Asher, PhD, professor of chemistry at the University of Pittsburgh Medical Center. "We're making great progress," Asher tells WebMD. "We expect to go to the FDA in another year. We're not sure how extensive clinical trials will need to be, given the experience with soft contact lenses."

Here's how it works: A thin plastic sensor is embedded in a typical soft contact lens; the type you replace weekly, explains Asher. The sensor detects the amount of glucose in the tears -- and changes color accordingly. On the eye, the sensor appears as a slim crescent of color in the lower area of the iris, below the pupil -- a hint of green (normal), blue (hypoglycemic - low blood sugar), or violet (very hypoglycemic). Other colors reflect high blood sugar levels, or hyperglycemia.

Asher's research group has performed "the definitive study confirming that tears can provide an accurate measurement of the body's glucose level," he tells WebMD. That was challenging, since tears resulting from any stressful trigger have a higher-than-normal amount of glucose. "If I make you cry, your tears are sweeter than normal," says Asher. His research group overcame the obstacle, developing their own innovative method to obtain sufficient normal tears for their study.

A Palm Pilot monitor or special mirror may be developed to help patients determine their exact glucose level. "No finger pricks are required," Asher tells WebMD. "In fact, this is more accurate than finger pricks because monitoring is continuous... the color keeps changing, letting you know if you're heading into hypoglycemia or hyperglycemia."

Glow-in-the Dark Tattoo

Tattoos inspired another novel device. The concept: Instead of just putting ink particles under the skin, why not put beads that would glow differently as glucose levels change in the body?

At Texas A&M University in College Station, engineers and chemists have developed fluorescent colored beads that do just that -- they glow differently as the blood glucose level changes, explains Gerard Cote, a biomedical engineering professor.

The beads are contained within a very thin, hair-like sheath. That sheath is inserted below skin level. When an LED light (on a wristwatch) shines on that area of skin, the beads glow -- their color revealing the glucose level. The LED monitor also registers the exact glucose value. An alarm would sound if you're nearing hypoglycemia.

Kids love the concept. There's a definite "cool factor," he tells WebMD. "Kids get so embarrassed about having to check their glucose around their friends. Now I've got kids saying, 'Tattoo me!'" One note: This 'tattoo' leaves no 'real' tattoo like a butterfly or heart -- kids will have to get that elsewhere.