Elution Solvent System for Florisil Column Cleanup in Organochlorine Pesticide Residue Analyses

Abstract

Abstract An elution solvent system is presented which can replace the currently used mixtures of ethyl ether-petroleum ether in the Florisil column chromatographic cleanup for pesticide residue analyses. Three eluants consisting of different mixtures of methylene chloride, hexane, and acetonitrile give greatly improved cleanup for extracts of fats and oils and recover pesticide chemicals of a greater range of polarity than do the ethyl ether-petroleum ether eluants. Fifty chemicals are known to be essentially completely recovered. Data are presented on fractional elution of representative compounds and on efficiency of removal of fatty substances. The proposed system has performed satisfactorily as a replacement for the ethyl ether-petroleum ether eluants in the analyses of a variety of representative foods for organochlorine pesticides.