Projects per year
Abstract
Fears of terrorist attacks have led to the development of various technologies for the real-time detection of explosives, but all suffer from potential ambiguities in the assignment of threat agents. Using proton transfer reaction mass spectrometry (PTR-MS), an unusual bias dependence in the detection sensitivity of 2,4,6 trinitrotoluene (TNT) on the reduced electric field (E/N) has been observed. For protonated TNT, rather than decreasing signal intensity with increasing E/N, which is the more usual sensitivity pattern observed in PTR-MS studies, an anomalous behavior is first observed, whereby the signal intensity initially rises with increasing E/N. We relate this to unexpected ion-molecule chemistry based upon comparisons of measurements taken with related nitroaromatic compounds (1,3,5 trinitrobenzene, 1,3 dinitrobenzene, and 2,4 dinitrotoluene) and electronic structure calculations. This dependence provides an easily measurable signature that can be used to provide a rapid highly selective analytical procedure to minimize false positives for the detection of TNT. This has major implications for Homeland Security and, in addition, has the potential of making instrumentation cost-effective for use in security areas. This study shows that an understanding of fundamental ion-molecule chemistry occurring in low-pressure drift tubes is needed to exploit selectivity and sensitivity for analytical purposes.
Original language | English |
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Pages (from-to) | 4161-4166 |
Number of pages | 6 |
Journal | Analytical Chemistry |
Volume | 84 |
Issue number | 9 |
DOIs | |
Publication status | Published - 1 May 2012 |
Bibliographical note
Copyright 2012 Elsevier B.V., All rights reserved.Fingerprint
Dive into the research topics of 'Proton transfer reaction mass spectrometry and the unambiguous real-time detection of 2,4,6 trinitrotoluene'. Together they form a unique fingerprint.Projects
- 1 Finished
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Fundamentals, Development and Application of Ion Mobility Spectrometry (IMS) foe Enhanced Trace Detection of Threat Agents
Mayhew, C. & Watts, P.
Engineering & Physical Science Research Council
1/09/07 → 29/02/12
Project: Research Councils