Determination of endogenous methane formation by photoacoustic spectroscopy
Abstract
Aerobic methane generation was demonstrated earlier in plants and eukaryotes under various stress conditions. Our aims were to develop a real-time and noninvasive detection system for monitoring the methane production of small animals and humans with our without exposure to various treatments. A near-infrared diode laser technique was employed with photoacoustic spectroscopy to monitor a methane-containing atmosphere online. The whole-body methane generation of anesthetized mice and rats was determined under baseline conditions and following reduction of the intestinal methanogenic flora or after lipopolysaccharide administration. Single-breath methane analyses were also carried out in a cross-sectional clinical study in order to obtain comparative human data. The whole-body methane production of mice was significantly decreased after antibiotic treatment (M: 1.71 ppm cm-2 103 p25: 1.5 ppm cm-2 103 p75: 2.11 ppm cm-2 103) and increased significantly in endotoxemia (M: 4.53 ppm cm-2 103 p25: 4.37 ppm cm-2 103 p75: 5.38 ppm cm-2 103), while no difference was observed between the rat groups. The methane content of the exhaled breath in humans was found to be between 0 and 37 ppm. Photoacoustic spectroscopy is a reliable tool with which to monitor the in vivo dynamics of stress-induced methane production in laboratory animals, even in a very low concentration range.
- Publication:
-
Journal of Breath Research
- Pub Date:
- December 2013
- DOI:
- 10.1088/1752-7155/7/4/046004
- Bibcode:
- 2013JBR.....7d6004T