Solid-phase microextraction gas chromatography for determination of some organophosphorus pesticides

A simple and rapid solid-phase microextraction (SPME) method is presented based on activated charcoal-PVC fiber for determination of some organopkosphorus pesticides from aqueous samples in direct mode SPME. After optimization of the experimental variables affecting SPME of the target compounds from aqueous solutions, the proposed method was applied to determine pesticides in fruit juice. The analytes in this procedure were preconcentrated for 15 min on the SPME fiber and subsequently desorbed by heating the fiber at 200 degreesC for 5 min in the GC injection port. Separation was on a capillary column GC followed by flame ionization detection. Recoveries of the pesticides studied in aqueous samples ranged 42%-63% and repeatability for all analytes was < 9% for a single fiber. Fiber-to-fiber reproducibility was < 18%.