AUTOMATED HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY FOR THE DETERMINATION OF PESTICIDES IN WATER USING SOLID-PHASE EXTRACTION

An automated solid phase extraction/high-performance liquid chromatography (SPE/HPLC) method has been developed to determine trace concentrations of Propoxur, Carbofuran, Carbaryl, Propham, Captan, Chloropropham, Barban, and Butylate In water. One hundred milliliters of sample water is passed through a disposable SPE cartridge packed with 90-μm sorbent at 10 mL/min. The concentrated analytes are eluted from the cartridge with acetonitrile. The resulting eluate Is blown-down under nitrogen, made up In water, and Injected Into the HPLC. The analytes are separated on a 25-cm C8 analytical column and determined by UV absorption at 220 nm. The total analytical time Is 90 min and the lowest detectable concentrations are in the range of 0.02—0.92 μg/L for the eight pesticides. Recoveries for the eight pesticides ranged from 84% to 93%. The procedure is totally automated and can analyze 30 samples consecutively and unattended. © 1990, American Chemical Society. All rights reserved.