Online recording of ethane traces in human breath via infrared laser spectroscopy

• Published in: Journal of applied physiology (1985) Vol. 95; no. 6; pp. 2583 - 2590
• Main Authors: von Basum, Golo, Dahnke, Hannes, Halmer, Daniel, Hering, Peter, Murtz, Manfred
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.12.2003; American Physiological Society
• Subjects: Adult; Algorithms; Biological and medical sciences; Breath tests; Breath Tests - instrumentation; Breath Tests - methods; Data Interpretation, Statistical; Ethane - metabolism; Fundamental and applied biological sciences. Psychology; Humans; Lasers; Lipid Peroxidation - physiology; Male; Online data bases; Oxidation; Oxidative Stress - physiology; Pulmonary Alveoli - metabolism; Respiratory system; Spectrophotometry, Infrared; Spectrum analysis; Human; Oxidative stress; Vertebrata; Mammalia; breath analysis; Lipids; alveolar slope; lipid peroxidation; Ethane; washout; Peroxidation; cavity leak-out spectroscopy
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00542.2003

Institut für Lasermedizin, Heinrich-Heine Universität Düsseldorf, D-40225 Düsseldorf, Germany Submitted 21 May 2003 ; accepted in final form 31 July 2003 A method is described for rapidly measuring the ethane concentration in exhaled human breath. Ethane is considered a volatile marker for lipid peroxidation. The breath samples are analyzed in real time during single exhalations by means of infrared cavity leak-out spectroscopy. This is an ultrasensitive laser-based method for the analysis of trace gases on the sub-parts per billion level. We demonstrate that this technique is capable of online quantifying of ethane traces in exhaled human breath down to 500 parts per trillion with a time resolution of better than 800 ms. This study includes what we believe to be the first measured expirograms for trace fractions of ethane. The expirograms were recorded after a controlled inhalation exposure to 1 part per million of ethane. The normalized slope of the alveolar plateau was determined, which shows a linear increase over the first breathing cycles and ends in a mean value between 0.21 and 0.39 liter -1 . The washout process was observed for a time period of 30 min and was modelled by a threefold exponential decay function, with decay times ranging from 12 to 24, 341 to 481, and 370 to 1,770 s. Our analyzer provides a promising noninvasive tool for online monitoring of the oxidative stress status. alveolar slope; breath analysis; cavity leak-out spectroscopy; lipid peroxidation; oxidative stress; washout Address for reprint requests and other correspondence: M. Mürtz, Universität Düsseldorf, Institut für Lasermedizin, Universitätsstra e 1, D-40225 Düsseldorf, Germany (E-mail: muertz{at}uni-duesseldorf.de ).