Capillary ion electrophoresis screening of nerve agent degradation products in environmental samples using conductivity detection.

A method of detecting signature methylphosphonic acid (MPA) breakdown products of V and G nerve agents in environmental samples was developed using capillary ion electrophoresis with conductivity detection. The electrolyte (30 mM L-histidine, 30 mM 2-(N-morpholino)ethanesulfonic acid, 0.7 mM tetradecyltrimethylammonium hydroxide, and 0.03 weight% Triton X-100) allowed baseline separation of MPA, ethyl methylphosphonic acid (EMPA), isopropyl methylphosphonic acid (IMPA), and pinacolyl methylphosphonic acid (PMPA) in less than 10 min. Detector response was linear in the 6-60 micrograms/ml concentration range (correlation coefficient = 0.99) with a detection limit around 6 micrograms/ml. The application of this method for screening MPA, EMPA, IMPA, and PMPA in surface water, groundwater, and soil extracts is demonstrated.