AUTOMATED GEL-PERMEATION CHROMATOGRAPHIC PREPARATION OF VEGETABLES, FRUITS, AND CROPS FOR ORGANOPHOSPHATE RESIDUE DETERMINATION UTILIZING FLAME PHOTOMETRIC DETECTION

A sensitive, flame photometric procedure for organophosphate residue determination using automated gel permeation chromatographic cleanup is described. Elution volumes of 26 parent and major metabolites of 4 representative organophosphates were determined. Fortification of 12 sample types with 6 parent compounds and 1 metabolite at 0.05-0.10 ppm yielded average recoveries of 83-103%. To demonstrate applicability of the method to multiresidue screening, 3 samples were fortified with 8 organophosphates and analyzed simultaneously.