Determination of chlorinated acid herbicides and related compounds in water by capillary electrophoresis-electrospray negative ion mass spectrometry

Capillary electrophoresis electrospray negative ion mass spectrometry was i nvestigated for the determination of chlorinated acid herbicides and severa l phenols in water. Sixteen analytes were separated as their anions in less than 40 min with a buffer consisting of 5 mM ammonium acetate in isopropan ol-water (40:60, v/v) at pH 10. A sample stacking technique was used to pro vide lower detection limits and a fortified drinking water sample was made pH 10 and analyzed without further processing. Quantitative analyses with a n internal standard gave recoveries in the 91-124% range and replicate meas urements of a calibration standard gave relative standard deviations in the range of 3-10%. (C) 1998 Elsevier Science B.V. All rights reserved.