Identification of Sarin and Related Compounds in Snow by Packed Capillary Liquid Chromatography-Electrospray Mass Spectrometry (LC-ESI-MS)

摘要

Packed capillary LC-ESl-MS was used for the analysis of a snow sample that was accidentally contaminated with an organophosphorus chemical warfare agent during the destruction of a chemical munition. Sarin, its hydrolysis products and a number of unique related compounds were identified on the basis of acquired LC-ESl-MS data. Full mass spectra were acquired for all fourteen compounds detected, with all compounds exhibiting MH+, MH+ACN+ ions and/or protonated dimers that could be used to confirm molecular mass. Sampling cone voltages from 20 to 70 volts were utilized with the higher sampling voltages enhancing formation of structurally important product ions in the ESI interface. All data were acquired with a time-of-flight (TOF) mass spectrometer with a resolution of 5000 (50% valley definition), a resolution that aided in the assignment of elemental composition of the observed ions. The application of LC- ESl-MS to snow analysis appears to be an attractive alternative to the GC-MS methods, since both chemical warfare agents and their hydrolysis products may be analysed directly, eliminating the need for additional sample handling and derivatization steps.