Desorption electrospray ionisation mass spectrometric analysis of chemical warfare agents from solid-phase microextraction fibers

Desorption electrospray ionisation mass spectrometry (DESI-MS) was recently reported for the direct analysis of sample media without the need for additional sample handling. During the present study, direct analysis of solid-phase microextraction (SPME) fibers by DESI-MS/MS was evaluated with indoor office media that might be collected during a forensic investigation, including wall surfaces, office fabrics, paper products and Dacron swabs used for liquid sampling. Media spiked at the mu g/g level with purified chemical warfare agents and a complex munitions grade sample of tabun, to simulate the quality of chemical warfare agent that might be used for terrorist purposes, were successfully analysed by DESI-MS/MS. Sulfur mustard, a compound that has not been successfully analysed by electrospray mass spectrometry in the past, was also sampled using a SPME fiber and analysed for the first time by DESI-MS/MS. Finally, the overall analytical approach involving SPME headspace sampling and DESI-MS analysis was evaluated during a scenario-based training live agent exercise. A sarin sample collected by the military was analysed and confirmed by DESI-MS in a mobile laboratory under realistic field conditions. Copyright (c) 2007 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.