| Title: | Selected Ion Flow-Drift Tube Mass Spectrometry: Quantification of Volatile Compounds in Air and Breath |
| Author(s): | Spesyvyi A; Smith D; Spanel P; |
| Address: | "J. Heyrovsky Institute of Physical Chemistry, the Czech Academy of Sciences , Dolejskova 3, 18223 Prague 8, Czech Republic. Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University in Prague , V Holesovickach 2, 18000 Prague, Czech Republic. Institute for Science and Technology in Medicine, School of Medicine, Keele University , Thornburrow Drive, Hartshill, Stoke-on-Trent ST4?ª+7QB, United Kingdom" |
| DOI: | 10.1021/acs.analchem.5b02994 |
| ISSN/ISBN: | 1520-6882 (Electronic) 0003-2700 (Linking) |
| Abstract: | "A selected ion flow-drift tube mass spectrometric analytical technique, SIFDT-MS, is described that extends the established selected ion flow tube mass spectrometry, SIFT-MS, by the inclusion of a static but variable E-field along the axis of the flow tube reactor in which the analytical ion-molecule chemistry occurs. The ion axial speed is increased in proportion to the reduced field strength E/N (N is the carrier gas number density), and the residence/reaction time, t, which is measured by Hadamard transform multiplexing, is correspondingly reduced. To ensure a proper understanding of the physics and ion chemistry underlying SIFDT-MS, ion diffusive loss to the walls of the flow-drift tube and the mobility of injected H3O(+) ions have been studied as a function of E/N. It is seen that the derived diffusion coefficient and mobility of H3O(+) ions are consistent with those previously reported. The rate coefficient has been determined at elevated E/N for the association reaction of the H3O(+) reagent ions with H2O molecules, which is the first step in the production of H3O(+)(H2O)1,2,3 reagent hydrate ions. The production of hydrated analyte ion was also experimentally investigated. The analytical performance of SIFDT-MS is demonstrated by the quantification of acetone and isoprene in exhaled breath. Finally, the essential features of SIFDT-MS and SIFT-MS are compared, notably pointing out that a much lower speed of the flow-drive pump is required for SIFDT-MS, which facilitates the development of smaller cost-effective analytical instruments for real time breath and fluid headspace analyses" |
| Keywords: | Air/*analysis Breath Tests/instrumentation/*methods Hydrogen-Ion Concentration Mass Spectrometry/instrumentation/*methods Volatile Organic Compounds/*analysis Water/chemistry; |
| Notes: | "MedlineSpesyvyi, Anatolii Smith, David Spanel, Patrik eng Research Support, Non-U.S. Gov't 2015/11/20 Anal Chem. 2015 Dec 15; 87(24):12151-60. doi: 10.1021/acs.analchem.5b02994. Epub 2015 Dec 3" |
