Detection of a chemical warfare agent simulant in various aerosol matrixes by ion mobility time-of-flight mass spectrometry

Abstract

For the first time, a traditional radioactive nickel (63Ni) β emission ionization source for ion mobility spectrometry was employed with an atmospheric pressure ion mobility orthogonal reflector time-of-flight mass spectrometer (IM-(tof)MS) to detect a chemical warfare agent (CWA) simulant from aerosol samples. Aerosol-phase sampling employed a quartz cyclonic chamber for sample introduction. The simulant reference material, which closely mimicked the characteristic chemical structure of CWAs as defined and described by Schedule 1, 2, or 3 of the Chemical Warfare Convention treaty verification, was used in this study. An overall elevation in arbitrary signal intensity of ∼1.0 orders of magnitude was obtained by the progressive increase of the thermal AP-IMS temperature from 75 to 275 ∼C. A mixture of one G-type nerve simulant (dimethyl methylphosphonate (DMMP)) in four (water, kerosene, gasoline, diesel) matrixes was found in each case (AP-IMS temperature 75-275 °C) to be clearly resolved in less than 2.20 × 104 μs using the IM(tof)MS instrument. Corresponding ions, masses, drift times, Ko values, and arbitrary signal intensities for each of the sample matrixes are reported for the CWA simulant DMMP. © 2005 American Chemical Society.