Laser light may be able to detect diseases on ...( WASHINGTON Feb. 15A team of scientis...),Health

WASHINGTON, Feb. 15A team of scientists at JILA, a joint institute of the National Institute of Standards and Technology (NIST) and the University of Colorado (CU) at Boulder, has shown that by sampling a persons breath with laser light they can detect molecules in the breath that may be markers for diseases like asthma or cancer. While many studies have been done to showcase the potential of optical technologies for breath analysis, the JILA approach takes an important step toward demonstrating the full power of optics for this prospective medical application. Their findings are published in the latest issue of the Optical Society of Americas open-access journal Optics Express.

The technique, called cavity-enhanced direct optical frequency comb spectroscopy, may one day allow doctors to screen people for certain diseases simply by sampling their breath. This technique can give a broad picture of many different molecules in the breath all at once, says Jun Ye, who led the research. He is a fellow of JILA, a fellow of NIST and a professor adjoint at CU-Boulders Department of Physics.

Optical frequency comb spectroscopy was developed in the 1990s by Yes JILA colleague John L. Hall and Theodor W. Hnsch of Germanys Max-Planck Institute (they shared the 2005 Nobel Prize in Physics with Roy J. Glauber for their invention). In the paper, Michael Thorpe, a graduate research assistant, Ye, and their colleagues describe the novel application of this technique to breath analysis. Optical comb spectroscopy is powerful enough to sort through all the molecules in human breath, Ye says, but it is also sensitive enough to find those rarest molecules that may be markers of specific diseases.

Every time we breathe in, we inhale a complex mixture of gassesmostly nitrogen, oxygen, carbon dioxide, and water vapor, but also traces of other gasses, such as carbon monoxide, nitrous oxide, and methane. Each time we exhale, we blow out a slightly different m
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