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Anal Bioanal Chem

Title:		Human breath analysis: methods for sample collection and reduction of localized background effects
Author(s):		Martin AN; Farquar GR; Jones AD; Frank M;
Address:		"Lawrence Livermore National Laboratory, Livermore, CA 94550, USA"
Journal Title:		Anal Bioanal Chem
Year:		2010
Volume:		20091022
Issue:		2
Page Number:		739 - 750
DOI:		10.1007/s00216-009-3217-7
ISSN/ISBN:		1618-2650 (Electronic) 1618-2642 (Linking)
Abstract:		"Solid-phase microextraction (SPME) was applied, in conjunction with gas chromatography-mass spectrometry, to the analysis of volatile organic compounds (VOCs) in human breath samples without requiring exhaled breath condensate collection. A new procedure, exhaled breath vapor (EBV) collection, involving the active sampling and preconcentration of a breath sample with a SPME fiber fitted inside a modified commercial breath-collection device, the RTube, is described. Immediately after sample collection, compounds are desorbed from the SPME fiber at 250 degrees C in the GC-MS injector. Experiments were performed using EBV collected at -80 degrees C and at room temperature, and the results compared to the traditional method of collecting exhaled breath condensate at -80 degrees C followed by passive SPME sampling of the collected condensate. Methods are compared in terms of portability, ease-of-use, speed of analysis, and detection limits. The need for a clean air supply for the study subjects is demonstrated using several localized sources of VOC contaminants including nail polish, lemonade, and gasoline. Various simple methods to supply clean inhaled air to a subject are presented. Chemical exposures are used to demonstrate the importance of providing cleaned air (organic vapor respirator) or an external air source (tubing stretched to a separate room). These techniques allow for facile data interpretation by minimizing background contaminants. It is demonstrated herein that this active SPME breath-sampling device provides advantages in the forms of faster sample collection and data analysis, apparatus portability and avoidance of power or cooling requirements, and performance for sample collection in a contaminated environment"
Keywords:		Adult Breath Tests/*instrumentation Gas Chromatography-Mass Spectrometry Humans Solid Phase Microextraction/*methods Specimen Handling/*methods;
Notes:		"MedlineMartin, Audrey N Farquar, George R Jones, A Daniel Frank, Matthias eng Evaluation Study Research Support, U.S. Gov't, Non-P.H.S. Germany 2009/10/22 Anal Bioanal Chem. 2010 Jan; 396(2):739-50. doi: 10.1007/s00216-009-3217-7. Epub 2009 Oct 22"