Detection of small trace molecules in human and animal's exhalation by tunable diode lasers

摘要

Abstract: Tunable diode laser spectroscopy (TDLS) is proposed for content measurements of trace gases like CO, CO$-2$/, NH$-3$/, CH$-4$/, NO, NO$-2$/ in human and animal's exhalation. High sensitivity and wide dynamic range of the method ensure fast detection of these gases at ppb level and within the accuracy better than 10%. One-expiration sample is enough to reach these parameters. There is no need for any preliminary preparation of tested samples. Some pairs of the gases, for instance, CO and CO$-2$/, NH$-3$/, and CO$-2$/, and CO and N$-2$/O, can be measured simultaneously by one laser providing complex studies. The high sensitive gas analysis could provide necessary background to the noninvasive diagnostics in a wide variety of medical problems. Perspectives of the TDLS methods in application to medicine diagnostics are demonstrated by the first results of exhalation tests. !19