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MS: Fachverband Massenspektrometrie
MS 8: Poster
MS 8.15: Poster
Donnerstag, 11. März 2010, 16:00–18:00, Lichthof
Distinguishing isomers and entering the ppqv detection limit region - latest developments in PTR-MS instruments — Alfons Jordan1, Philipp Sulzer1, Simone Jürschik1, Stefan Jaksch1, Gernot Hanel1, Eugen Hartungen1, Hans Seehauser1, •Lukas Märk1, Stefan Haidacher1, Ralf Schottkowsky1, and Tilmann Märk1,2 — 1IONICON Analytik GmbH, Technikerstr. 21a, 6020 Innsbruck, Austria — 2Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria
We report on the latest instrumental developments, namely i) the improvement of the detection limit that now allows for measuring trace gas compounds in a concentration range from several ppmv down to the ppqv (parts-per-quadrillion) region with a typical response time well below 100ms and, in case a TOF mass analyzer is used, a mass resolution better than 5.000 m/Δm and ii) the possibility to switch between H3O+, NO+ and O2+ as reagent ions. We show, that the sensitivities obtained with NO+ and O2+ are comparable or even better to the outstanding sensitivity of the established PTR-MS instruments and therefore well above those from e.g. SIFT-MS instruments. To demonstrate the advantages of the new setup we e.g. measured acetone and propanal (isomeric molecules at nominal mass 58amu) utilizing NO+ as the precursor ion. We see the isomeric compounds on different nominal masses and can identify them unambiguously. Furthermore, by using O2+ precursor ions we are able to ionize molecules that cannot be measured via hydronium proton transfer reaction.