Gas chromatography-mass spectrometric analysis of trimethylsilyl derivatives of toxic hydrolyzed products of nerve agent VX and its analogues for verification of Chemical Weapons Convention

[摘要] The formation of trimethylsilyl (TMS) derivative of hydrolyzed product of nerve agent VX, namely S-2-(N,N-diisopropylaminoethyl) methylphosphonothiolate (EA-2192), was reported to be hampered due to its zwiterionic character. Contrary to this assumption, we have synthesized and analyzed the TMS derivative of EA-2192 and its analogues. Initially, the problem of non-detectability in GC-MS analysis was found to be due to their condensation followed by decomposition on GC column. An optimized temperature program, starting from 175 °C column temperature, favours partitioning of TMS derivatives of EA-2192 and its analogues into mobile phase, which facilitates their detection. It reduces their on-column condensation and decomposition. Excellent reproducibility (<1% RSD) of TMS derivatives of S-2-(N,N-dialkylaminoethyl) alkylphosphonothiolates was achieved by GC-MS analysis with temperature program of 175 °C (2 min)–10 °C min−1– 300 °C (5 min). Under the optimized conditions LODs ranged from 8–10 μg mL−1 for different analytes at a split ratio of 1 : 10...

[学科分类] 分析化学