| Title: | Unambiguous identification of volatile organic compounds by proton-transfer reaction mass spectrometry coupled with GC/MS |
| Author(s): | Lindinger C; Pollien P; Ali S; Yeretzian C; Blank I; Mark T; |
| Address: | "Nestle Research Center, Vers-chez-les-Blanc, 1000 Lausanne 26, Switzerland" |
| ISSN/ISBN: | 0003-2700 (Print) 0003-2700 (Linking) |
| Abstract: | "Interest in on-line measurements of volatile organic compounds (VOCs) is increasing, as sensitive, compact, and affordable direct inlet mass spectrometers are becoming available. Proton-transfer reaction mass spectrometry (PTR-MS) distinguishes itself by its high sensitivity (low ppt range), high time resolution (200 ms), little ionization-induced fragmentation, and ionization efficiency independent of the compound to be analyzed. Yet, PTR-MS has a shortcoming. It is a one-dimensional technique that characterizes compounds only via their mass, which is not sufficient for positive identification. Here, we introduce a technical and analytical extension of PTR-MS, which removes this shortcoming, while preserving its salient and unique features. Combining separation of VOCs by gas chromatography (GC) with simultaneous and parallel detection of the GC effluent by PTR-MS and electron impact MS, an unambiguous interpretation of complex PTR-MS spectra becomes feasible. This novel development is discussed on the basis of characteristic performance parameters, such as resolution, linear range, and detection limit. The recently developed drift tube with a reduced reaction volume is crucial to exploit the full potential of the setup. We illustrate the performance of the novel setup by analyzing a complex food system" |
| Keywords: | Coffee/chemistry Gas Chromatography-Mass Spectrometry/*methods Organic Chemicals/*analysis Volatilization; |
| Notes: | "MedlineLindinger, Christian Pollien, Philippe Ali, Santo Yeretzian, Chahan Blank, Imre Mark, Tilmann eng 2005/07/01 Anal Chem. 2005 Jul 1; 77(13):4117-24. doi: 10.1021/ac0501240" |
