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Extraction and detection of the volatile chemical markers of explosives with a novel planar geometry solid phase microextraction device coupled to ion mobility spectrometry

NCJ Number
Journal of Separation Sciences Volume: 31 Dated: 2008 Pages: 2891-2898
Date Published
8 pages

This article reports for the first time novel planar geometry solid phase microextraction (SPME) devices coated with PDMS and sol–gel PDMS that do not require an additional interface to ion mobility spectrometry (IMS).


Ion mobility spectrometry (IMS) is routinely used in screening checkpoints for the detection of explosives and illicit drugs, but it mainly relies on the capture of particles on a swab surface for the detection. Solid phase microextraction (SPME) has been coupled to IMS for the preconcentration of explosives and their volatile chemical markers; however, although it has improved the LODs over a standalone IMS, it is limited to sampling in small vessels by the fiber geometry. In the project reported in this article, the explosive, 2,4,6‐trinitrotoluene (TNT), was sampled with the planar SPME reaching extraction equilibrium faster than with fiber SPME, concentrating detectable levels of TNT in a matter of minutes. The surface area, capacity, extraction efficiency, and LODs were also improved over fiber SPME, enabling sampling in larger volumes. The volatile chemical markers, 2,4‐dinitrotoluene, cyclohexanone, and the taggant 4‐nitrotoluene have also been successfully extracted by planar SPME and detected by IMS at mass loadings below 1 ng of extracted analyte on the planar device for TNT, for example. (publisher abstract modified)

Date Published: January 1, 2008