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Drift tube ion mobility spectrometry with a novel atmospheric electron emission (AEE) source was developed for determination of gaseous and blister chemical warfare agents (CWAs) in negative mode. The AEE source was fabricated from an aluminum substrate electrode covered with 1 μm silver nanoparticle-dispersed silicone resin and a thin gold layer. This structure enabled stable tunneling electron emission upon the application of more than 11 V potential under atmospheric pressure. The reactant ion peak (RIP) was observed for the reduced mobility constant (K 0) of 2.18 and optimized at the charging voltage of 20 V. This RIP was assigned to O2 – by using a mass spectrometer. Hydrogen cyanide was detected as a peak (K 0 = 2.47) that was discriminatively separated from the RIP (resolution = 1.4), with a limit of detection (LOD) of 0.057 mg/m3, and assigned to CN– and OCN–. Phosgene was detected as a peak (K 0 = 2.36; resolution = 1.2; and LOD = 0.6 mg/m3), which was assigned to Cl–. Lewisite 1 was detected as two peaks (K 0 = 1.68 and 1.34; LOD = 12 and 15 mg/m3). The K 0 = 1.68 peak was ascribed to a mixture of adducts of molecules or the product of hydrolysis with oxygen or chloride. Cyanogen chloride, chlorine, and sulfur mustard were also well detected. The detection performance with the AEE source was compared with those under corona discharge and 63Ni ionizations. The advantage of the AEE source is the simple RIP pattern (only O2 –), and the characteristic marker ions contribute to the discriminative CWAs detection.

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A field-portable gas chromatography-mass spectrometry (GC-MS) system (Hapsite ER) was evaluated for the detection of nonvolatile V-type nerve agents (VX and Russian VX (RVX)) in the vapor phase. The Hapsite ER system consists of a Tri-Bed concentrator gas sampler, a nonpolar low thermal-mass capillary GC column and a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump. The GC-MS system was attached to a VX-G fluoridating conversion tube containing silver nitrate and potassium fluoride. Sample vapors of VX and RVX were converted into O-ethyl methylphosphonofluoridate (EtGB) and O-isobutyl methylphosphonofluoridate (iBuGB), respectively. These fluoridated derivatives were detected within 10 min. No compounds were detected when the VX and RVX samples were analyzed without the conversion tube. A vapor sample of tabun (GA) was analyzed, in which GA and O-ethyl N,N-dimethylphosphoramidofluoridate were detected. The molar recovery percentages of EtGB and iBuGB from VX and RVX vapors varied from 0.3 to 17%, which was attributed to variations in the vaporization efficiency of the glass vapor container. The conversion efficiencies of the VX-G conversion tube for VX and RVX to their phosphonate derivatives were estimated to be 40%. VX and RVX vapors were detected at concentrations as low as 0.3 mg m . Gasoline vapor was found to interfere with the analyses of VX and RVX. In the presence of 160 mg m gasoline, the detection limits of VX and RVX vapor were increased to 20 mg m . Copyright © 2017 John Wiley & Sons, Ltd.