Lasers Detect Disease in Patient Breath

Feb. 22, 2008 -- Diagnosing life threatening diseases could soon be as easy as breathing.

Researchers at the National Institute for Standards and Technology and the University of Colorado are now using lasers to detect specific chemical compounds in the breath of patients with cancer, asthma and diabetes.

The technique, once perfected and commercialized, could save patients and insurance companies thousands of dollars and make disease diagnosis and monitoring faster and more efficient.

"We hope that the technology will develop to be a very useful tool for preventive medicine," said Jun Ye, a study author and a physics professor at the University of Colorado-Boulder. "It can provide an early warning system to potential patients."

The researchers use a technology known as an optical frequency comb. When a person breathes into a small chamber the scientists bombard the exhaled air with lasers of different wavelengths (making up the "comb"). Different sized laser beams excite specific compounds, which then emit different colors of light. These colors are read by another machine.

In a much simplified version of the technique, the researchers simply look and see what color the breath is after interacting with the comb and then diagnose a condition based on the color.

The laser test, described in the Feb. 18 online edition of Optics Express, is sensitive enough to detect a few molecules out of several billion.