UCF Professor Developing Teardrop Test for Diabetic Blood-Sugar Levels

A University of Central Florida chemistry and optics professor is developing a method to test blood-sugar levels in teardrops, a system that would allow diabetics to forgo painful daily finger pricks.

The simple teardrop test, which could be made available in stores at stations similar to the blood-pressure booths common in many pharmacies, could also provide a means for early detection of diabetes, Assistant Professor Florencio Hernandez said.

"It’s so simple, it’s wonderful," Hernandez said. The chemistry involves placing a teardrop in a gold-salt solution to generate gold nanoparticles. The solution is then loaded into a UV-Vis spectrophometer that reads the concentration of gold nanoparticles, which is directly proportional to the concentration of sugar. The spectrophotometer is smaller than a CD.

The reaction of the gold with the sugar is visible to the naked eye. Depending on the level of sugar in a person’s body, the solution will turn from light pink to a bloody red.

"I hope in two to three years to have prototypes out and that someday you’ll be able to go to a grocery store and test your sugar, just like you test your blood pressure," Hernandez said.

Not only is the method painless, it could also be used to detect rising sugar levels years before any symptoms might lead a patient to visit a doctor for a diabetes test. It could also provide an early alert for pregnant women at risk for gestational diabetes.

"That was the whole idea, to have it be preventative," Hernandez said. "That way, if you see a pattern you can address the problem before it really becomes grave, before the disease does a lot of damage."

Diabetes, type 1 and 2, affects 20.8 million people in America according to the Centers for Disease Control. It ranks as the sixth-leading cause of death nationally and can lead to heart disease, stroke, high blood pressure, blindness, kidney disease and nervous system disorders.

Pricking a finger to get a sample of blood, which is then loaded into a meter that reads the sugar level in the blood is the most common way diabetics monitor their sugar. For some it’s a daily routine, while for others it is required several times a day. It’s painful, especially for young children who are diagnosed with the disease.

Marisol Garcia, a graduate student at the time Hernandez came up with the new approach, also helped with the research. She has since graduated from the program. Now Hernandez is working on increasing the sensitivity of the technology. While the nanoparticles can detect sugar in urine, blood and saliva, the best mediums are teardrops. He’s also working to patent the technology.

Hernandez’s work was published in Chemical and Engineering News in April, and he presented it in March at the American Chemical Society national meeting in Atlanta. The article follows another piece published in January in which he describes his research into using gold nanoparticles to detect mercury in water.

Hernandez and UCF colleague Andres Campilglia found that they could detect even trace amounts of mercury in water using light and tiny pieces of gold. The findings are being used to develop water filters that will help clean contaminated water.

A segment featuring Hernandez and Campilglia’s work will be showcased next month in an upcoming video on Breakthroughs and Inside Science at http://discoveriesandbreakthroughs.org.

Hernandez hopes to partner on the glucose meter with a Florida hospital to begin animal and human testing in the next year or so.

"It’s all about understanding nature," Hernandez said of his work. "Everything is there; you just have to be a careful observer. But figuring out how it works, now that’s exciting."