Determination of six degradation products of nerve agents in human plasma using gas chromatography/mass spectrometry with strong anion exchange-solid phase extraction

For the unequivocal proof of the use of chemical warfare agents (CWA), a simple and accurate method was explored, which could simultaneously determine six degradation products of nerve agents in human plasma, using gas chromatography/mass spectrometry (GC/MS) after trimethylsilyl derivatization. GC/MS analysis was performed after solid-phase extraction with a strong anion-exchange cartridge from the plasma samples, which was previously deproteinized by mercuric acetate. The efficiency of various deproteinization reagents and the effect of different solid-phase extraction cartridges were investigated. The concentration of eluent was also optimized. Linear calibration curves were obtained for the five alkyl methylphosphonic acids and methyl phosponic acid over concentrations ranging from 50 mu g/L to 5 mg/L in selected ion monitoring mode, and the detection limits were within 22 mu g/L. The RSD were less than 9.7%. This method offers relatively high sensitivity and reliable reproducibility. Thus, it should become a powerful method for the rapid and sensitive detection of nerve agents in biological samples.