|University of Colorado at Boulder
physics doctoral student Michael Thorpe holds a detection chamber
while standing next to a laser apparatus in a photo released by the
university on Tuesday. A new laser analyzer might be able to help
doctors detect cancer, asthma or other diseases by sampling a
patient's breath, researchers reported on Tuesday.
By blasting a person's breath with laser light, U.S. scientists
have shown that they can detect molecules that may be markers for
diseases like asthma or cancer.
While the new technique has yet to be tested in clinical trials,
it may someday allow doctors to screen people for certain diseases
simply by sampling their breath, according to the research team
from JILA, a joint institute of the National Institute of Standards
and Technology and the University of Colorado at Boulder as quoted
by media Wednesday.
"This technique can give a broad picture of many different
molecules in the breath all at once," Jun Ye, who led the research
at the University of Colorado, said in a statement.
Ye's team developed a new technique, called cavity-enhanced
direct optical frequency comb spectroscopy.
When animals and people breathe out, they exhale not only gases
that are not needed, such as carbon dioxide, but also compounds
that result from the metabolism of cells.
"To date, researchers have identified over 1,000 different
compounds contained in human breath," Ye's team wrote in
Some point to abnormal function -- such as methylamine, produced
in higher amounts by liver and kidney disease, ammonia produced
when the kidneys are failing or elevated acetone caused by
People with asthma may produce too much nitric oxide, exhaled in
the breath, while smokers produce high levels of carbon
In 2006, researchers found dogs could be trained to smell cancer
on the breath of patients with 99 percent accuracy.
Ye's team used their method to analyze the breath of several
student volunteers and found they could detect trace signatures of
ammonia, carbon monoxide, and methane in breath.
(Agencies via Xinhua News Agency February 20, 2008)