Enantioseparation of the racemates of a number of pesticides on a silica-based column with immobilized amylose tris(3-chloro-5-methylphenylcarbamate)

Abstract

We report here the results from studies on the high-performance liquid chromatographic HPLC enantioresolution of thirty different types of pesticides on the chiral silica-based column with immobilized amylose tris(3-chloro-5-methylphenylcarbamate (ACMPC) (CHIRALPAK IG-3) under polar-organic and reversed-phase conditions measured at 20 °C. The main objective was to explore diverse polar and aqueous-based eluents for use with a single column to obtain an enantioseparation of polar pesticides usually found in environmental matrices. These pesticides included phenoxy- and aryloxyphenoxypropionic acids, imidazolinones, and diphenyl-ether herbicides; acylanilides, triazoles, and pyrimidine fungicides; chlordane and pyrethroid insecticides; organophosphorus compounds; and some metabolites and precursors. We obtained improved chromatographic enantioresolutions for seventeen of these compounds in either the polar-organic or reversed-phase modes, including six pesticides whose enantioseparation is reported for first time through the use of these chromatographic modes.