A novel headspace sampler for field detection of chemical warfare agents and simulants connected to a commercial ion mobility detector

Abstract

A rapid and simple sampling technique for use in conjunction with commercial ion mobility spectrometric detectors is described. The technique may be used for the detection of chemical warfare agents in the field. A plastic syringe with a steel needle was attached to the nozzle of the detector, and the syringe shortened to reduce the dead volume in the interface. After heating samples of protective clothing in closed headspace vials to 70 °C for three minutes, the detector with the syringe and needle (called HS-LCD) was used to penetrate the vial and the overpressure was transferred to the detector via the simple interface. The detector response was registered in realtime. To demonstrate the possibilities with this technique, the HS-LCD sampler was tested in the field at relatively low temperatures on pieces of protective clothing contaminated by the chemical warfare agent simulants methyl salicylate and dipropylene glycol methyl ether. A significant improvement in detector response was observed utilising this technique compared to using the detector to survey the material in the open air. This improvement is believed to increase with decreasing ambient temperature and with decreasing analyte volatility. A more comprehensive list of possible interferents should be tested in the future.