Lasers Detect Disease in Patient Breath

Scientists have known for years that certain diseases and conditions cause minute changes to a person's breath. Diseases cause physiologic changes inside the body, creating new chemical compounds that can either change the chemical composition of the air exiting the lungs, or add new chemicals that aren't found in healthy lungs.

Asthma patients will often exhale carbonyl sulfide, carbon monoxide, hydrogen peroxide and nitric oxide all together. Diabetics often have sweet smelling breath, the result of an inability to process certain sugars.

Even kidney failure and liver disease can change a person's breath at the molecular level. Figuring out the specific biochemical reactions that changes a person's breath is a hot topic of research, notes Ye.

"This is a new kind of non-invasive and shockingly inexpensive assay technique," said John Hall, a retired physics professor whose work with lasers earned him a 2005 Nobel Prize in Physics.

While the device is still being developed, Hall, who was not involved in the work, expects that a commercial version of the device would fit inside an average suitcase and cost between $30,000-50,000.

For his own interest, Hall had the researchers use the device to test his own breath for the presence of nitrate, which can indicate renal failure.

"I was terribly pleased to learn that I don't have it," he said.

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