Laser beams help discover hidden diseases through breathing patterns

Using lasers to break a person's breath, scientists at the National Institute of Standards and Technology (NIST) and the University of Colorado (CU) in Boulder have shown that they can find molecules can be illness signs like asthma or cancer.

While new techniques have not yet been tested by clinical trials, they will now allow doctors to review some diseases simply by sampling the breath according to the research team from JILA, an institute. cooperation of NIST and CU-Boulder. According to Jun Ye, a member of JILA and NIST, the new technique can produce a broad picture of many different molecules in an instant breath.

Michael Thorpe, CU-Boulder University assistant researcher, and Dr. Matthew Kirchner and former CU Master David Balslev-Clausen describe the study in an article that was available on February 18 edition of Optics Express , a free and open access journal released by the Optical Society of America. Known as spectroscopy, this technique is powerful enough to select in all the molecules in one's breath as well as being sensitive enough to distinguish rare molecules that can be biological markers for specific disease.

According to Ye, when breathing people inhale a mixture of complex gases including nitrogen, oxygen, carbon dioxide, steam and small amounts of other gases such as CO, N2O and methane . The exhaled breath contains less oxygen, more carbon dioxide and a large group of more than a thousand different types of molecules and most of them have only a small amount. Bad breath may indicate dental problems, excessive CH ₃ NH ₂ gas levels indicate liver and kidney diseases, ammonia gas may be a sign of kidney failure, high levels of acetone suggest fat Obesity and the amount of NO can be used to diagnose asthma.

Corolado University's Ph.D. student in Boulder is holding a magazine that detects near a strange laser device at JILA.(Photo: JILA, NIST, University of Colorado at Boulder)

When a lot of breath molecules are detected at the same time, high reliability, specific information about the disease can be gathered. For example, asthma can be found with high reliability when gas with OCS, CO, and H ₂ O _{2 components} is detected at the same time with NO. While current breath analyzes with biomarkers are a less expensive and 'non-invasive' procedure , methods are limited because media are not selective enough to find a wide variety of Rare or insensitive biomarkers to detect small amounts of molecules that have been breathed out in human breath.

He said that the new technology has the potential to be low cost, fast and reliable as well as sensitive enough to find a wider range of biomarkers immediately with a variety of diseases. Laser optical graphics are precise lasers to measure different colors or frequencies of light. Each line or ' teeth ' matches the specific frequency of the vibrations and revolutions of a particular molecule, and the sketch includes the entire spectrum of spectra like a colorful rainbow that can be Determine thousands of different molecules. Laser beams can detect and distinguish specific molecules because different molecules vibrate and rotate with a distinct sound resonance frequency that clearly depends on the composition and texture of the molecule . He showed great interest in the concept of different stations broadcasting at separate frequencies.

Optical frequency sketches were developed in 1990 by Ye of JILA, NIST and CU-Boulder colleagues John L. " Jan " Hall and Theodor W. Hänsch at the Max-Planck Institute of Germany who shared the prize. Nobel Prize in Physics with Roy J. Glauber about their joint work. Ye's group pioneered the application of frequency sketches to spectroscopy or the analysis of light emitted and absorbed by matter. As illustrated by Thorpe, Ye and colleagues in Science in 2006, the technique allows the detection of many different gases immediately with high sensitivity through interaction with light from sketches. like that.

To test the technology, Ye's group had several CU-Boulder volunteer students breathe into the optical cavity - a gap between the curved mirrors and then put ultrafast laser pulses into the cavity. When light pulses bounce around the cavity tens of thousands of times, researchers determine what frequency of light is absorbed, which indicates which molecules and their number are present thanks to the number The light they absorb.

Ye and colleagues detected small signs of gases such as ammonia, carbon dioxide, and methane from samples of volunteers. Ye said that, in one measurement, they detected carbon dioxide in a smoking student five times higher than a non-smoking student. ' Spectroscopic sketch is an application for analyzing human breath ' according to Michael J. Thorpe, in Optics Express, Term 16, No. 4, February 18, summarized at http:///www.opticsinfobase .org / abstract.cfm? URI = oe-16-4-2387.

Funding from the Air Force Office of Scientific Research, Agilent Technology Foundation (Agilent Technologies Foundation), the Defense Advanced Research Projects Agency, NIST, National Science Foundation and CU-Boulder.