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Scientific Articles - PTR-MS Bibliography

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Found 5 results
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[Juerschik2013] Juerschik, S., M. Lanza, P. Sulzer, B. Agarwal, E. Hartungen, A. Edtbauer, S. Feil, A. Jordan, G. Hanel, CA. Mayhew, et al., "Designer Drugs and Trace Explosives Detection with the Help of Very Recent Advancements in Proton-Transfer-Reaction Mass Spectrometry (PTR-MS)", CONFERENCE SERIES, pp. 182, 2013.
[Lindinger2011] Lindinger, C., B. Agarwal, F. Petersson, S. Juerschik, P. Sulzer, A. Jordan, P. Watts, CA. Mayhew, K. Becker, and TD. Märk, "Recent developments in Proton-Transfer-Reaction Mass Spectrometry leading to new fields of application (eg illicit and designer drugs detection)", : IONICON Analytik, 2011.
[Mayhew2010] Mayhew, CA., P. Sulzer, F. Petersson, S. Haidacher, A. Jordan, L. Maerk, P. Watts, and TD. Maerk, "Applications of proton transfer reaction time-of-flight mass spectrometry for the sensitive and rapid real-time detection of solid high explosives", International Journal of Mass Spectrometry, vol. 289, no. 1: Elsevier, pp. 58–63, 2010.
Using recent developments in proton transfer reaction mass spectrometry, proof-of-principle investigations are reported here to illustrate the capabilities of detecting solid explosives in real-time. Two proton transfer reaction time-of-flight mass spectrometers (Ionicon Analytik) have been used in this study. One has an enhanced mass resolution (m/Δm up to 8000) and high sensitivity (∼50 cps/ppbv). The second has enhanced sensitivity (∼250 cps/ppbv) whilst still retaining high resolution capabilities (m/Δm up to 2000). Both of these instruments have been successfully used to identify solid explosives (RDX, TNT, HMX, PETN and Semtex A) by analyzing the headspace above small quantities of samples at room temperature and from trace quantities not visible to the naked eye placed on surfaces. For the trace measurements a simple pre-concentration and thermal desorption technique was devised and used. Importantly, we demonstrate the unambiguous identification of threat agents in complex chemical environments, where multiple threat agents and interferents may be present, thereby eliminating false positives. This is of considerable benefit to security and for the fight against terrorism.
[Brown2010] Brown, P., P. Watts, TD. Märk, and CA. Mayhew, "Proton transfer reaction mass spectrometry investigations on the effects of reduced electric field and reagent ion internal energy on product ion branching ratios for a series of saturated alcohols", International Journal of Mass Spectrometry, vol. 294, no. 2: Elsevier, pp. 103–111, 2010.
In this paper we report an investigation of the effects of E/N over the range of 90–140 Td on the product ions resulting from the reactions of H3O+ with 12 saturated alcohols using a proton transfer reaction mass spectrometer (PTR-MS). The alcohols included in this study are methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 2-butanol, cyclopentanol, 1-pentanol, cyclohexanol, and 1-hexanol. Only in the cases of methanol and ethanol are any substantial amounts of the protonated parent observed at any E/N. For the other saturated alcohols predominantly fragment ions are observed. This implies that attempts to identify and hence monitor saturated alcohols in trace concentrations in a complex chemical environment using PTR-MS will be fraught with difficulties because a given m/z will not be unique to a particular chemical compound, i.e., multiple species could be present at a given m/z. In addition to changes in E/N we present preliminary results with regards to changing the conditions in the generation of the reagent ions via altering the operational conditions within the ion source (a hollow cathode). We present product ion branching ratios as a function of hollow cathode emission current for cyclohexanol, 1-propanol and 2-propanol at fixed E/N. Although not part of the reaction chamber, we have found that changing the hollow cathode emission current results in modifications to the product ion branching ratios. We presume that these observed changes are a result of altering the internal energies of the reagent ions and thereby modify the reaction kinetics and dynamics occurring within the drift tube of a PTR-MS.
[Critchley2004] Critchley, A., TS. Elliott, G. Harrison, CA. Mayhew, JM. Thompson, and T. Worthington, "The proton transfer reaction mass spectrometer and its use in medical science: applications to drug assays and the monitoring of bacteria", International Journal of Mass Spectrometry, vol. 239, no. 2: Elsevier, pp. 235–241, 2004.
Proton transfer reaction mass spectrometry (PTR-MS) enables monitoring of trace gases in air with high sensitivity without major gases interfering. In this paper, we present the potential use of a proton transfer reaction mass spectrometer for two medical applications; the monitoring of drugs and bacterial infection. The first study illustrates a feasibility trial to monitor the intravenous anaesthetic agent 2,6-di-isopropyl phenol (propofol), and two of its metabolites, on the breath of patients in real-time during surgery. Propofol is a commonly used intravenous anaesthetic. However, there is no method of instantaneously monitoring the plasma concentration of the agent during surgery, and therefore determining whether or not the plasma level is of such a value to ensure that the patient is correctly anaesthetized. That propofol and its metabolites were monitored in real-time using the PTR-MS suggests possibilities for routine intravenous anaesthesia monitoring analogous to that for volatile anaesthetic agents. In addition to the above work we also investigated proton transfer to another anaesthetic, sevoflurane. Comparisons between PTR-MS and selected ion flow tube (SIFT) investigations are presented. The second study presented in this paper investigated the volatile organic compounds emitted by microbial cell cultures. The objective was to show that different microbial cultures could be readily distinguished from the resulting mass spectra recorded using the PTR-MS. The initial results are encouraging, which taken together with the real-time analysis and high sensitivity of the PTR-MS, means that proton transfer reaction mass spectrometry has the potential to characterise bacterial infection rapidly.

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Selected PTR-MS related Reviews

F. Biasioli, C. Yeretzian, F. Gasperi, T. D. Märk: PTR-MS monitoring of VOCs and BVOCs in food science and technology, Trends in Analytical Chemistry 30 (7) (2011).

J. de Gouw, C. Warneke, T. Karl, G. Eerdekens, C. van der Veen, R. Fall: Measurement of Volatile Organic Compounds in the Earth's Atmosphere using Proton-Transfer-Reaction Mass Spectrometry. Mass Spectrometry Reviews, 26 (2007), 223-257.

W. Lindinger, A. Hansel, A. Jordan: Proton-transfer-reaction mass spectrometry (PTR–MS): on-line monitoring of volatile organic compounds at pptv levels, Chem. Soc. Rev. 27 (1998), 347-375.


Lists with PTR-MS relevant publications of the University of Innsbruck can be found here: Atmospheric and indoor air chemistry, IMR, Environmental Physics and Nano-Bio-Physics


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