QUANTITATIVE-ANALYSIS OF CHEMICAL WARFARE AGENT DEGRADATION PRODUCTS IN REACTION MASSES USING CAPILLARY-ELECTROPHORESIS

Quantitative methods have been developed for the analysis of chemical warfare agent degradation products in reaction masses using capillary electrophoresis (CE), This is the first report of a systematic validat ion of a CE-based method for the analysis of chemical warfare agent de gradation products in agent neutralization matrixes (reaction masses). After neutralization with monoethanolamine/water, the nerve agent GB (isopropyl methylphosphonofluoridate, Sarin) gives isopropyl methylpho sphonic acid (IMPA) and O-isopropyl O'-(2-amino)ethyl methylphosphonat e (GB-MEA adduct). The nerve agent GD (pinacolyl methylphosphonofluori date, Soman), [pinacolyl= 2-(3,3-dimethyl)butyl] produces pinacolyl me thylphosphonic acid (PMPA) and O-pinacolyl O'-(2-amino)ethyl methylpho sphonate (GD-MEA adduct), The samples were prepared by dilution of the reaction masses with deionized water before analysis by CE/indirect U V detection or CE/conductivity detection. Migration time precision was less than 4.0% RSD for IMPA and 5.0% RSD for PMPA on a day-to-day bas is. The detection limit for both IMPA and PMPA is 100 mu g/L; the quan titation limit for both is 500 mu g/L. For calibration standards, IMPA and PMPA gave a linear response (R-2 = 0.9999) over the range 0.5-100 mu g/mL. The interday precision RSDs were 1.9, 1.0, and 0.7% for IMPA at 7.5, 37.5 and 75.0 mu g/mL, respectively, Corresponding values for PMPA (again, RSD) were 2.9, 1.1, and 1.0% at 7.5, 37.5 and 87.5 mu g/ mL, respectively, as before. Analysis accuracy was assessed by spiking actual neutralization samples with IMPA or PMPA. For IMPA, the seven spike levels used ranged from 20 to 220% of the IMPA background level, and the incremental change in the found IMPA level ranged from 86 to 99% of the true spiking increment (R2 = 0.9987 for the linear regressi on). For PMPA, the five spike levels ranged from 10 to 150% of the mat rix background level, and similarly, the accuracy obtained ranged from 95 to 97% of the true incremental value (R-2 = 0.9999 for the linear regression).