Development and use of a thermal desorption unit and proton transfer reaction mass spectrometry for trace explosive detection: Determination of the instrumental limits of detection and an investigation of memory effects

作者：Gonzalez Mendez Ramon; Reich D Fraser; Mullock Stephen J; Corlett Clive A; Mayhew Chris A^*

来源：International Journal of Mass Spectrometry, 2015, 385: 13-18.

DOI：10.1016/j.ijms.2015.05.003

• Proton transfer reaction mass spectrometry
• (PTR-MS)
• Explosives
• Explosives detection
• Thermal desorption unit

A novel thermal desorption unit (TDU) has been developed and specifically designed for the detection of trace quantities of explosives using a proton transfer reaction mass spectrometer (PTR-MS). For the first time details on recovery times and instrumental limits of detection for the screening of explosives with this TDU/PTR-MS system are reported. We demonstrate that traces (nanograms or less) of explosives deposited on swabs are desorbed within less than a second upon insertion into the TDU. For a short period of time (seconds) a concentration "pulse" of an explosive enters the drift (reaction) tube of the PTR-MS. This temporal concentration pulse of material is monitored in real-time by recording the product ion intensities for a given explosive as a function of time. By changing the reduced electric field in the drift tube region of the PTR-MS, we demonstrate how selectivity can be improved. This study demonstrates that the TDU/PTR-MS instrument meets security application criteria in terms of sensitivity, selectivity and recovery times.

• 出版日期2015-6-15