Analysis of Chlorimuron Ethyl and Tribenuron Methyl in Crops by HPLC with a Photodiode Array Detector

An analytical method for determination of sulfonylurea herbicides, chlorimuron ethyl (CE) and tribenuron methyl (TM), in crops by HPLC was developed.The sample was homogenized with acetone followed by extraction with ethyl acetate, and the extract was evaporated. The residue was defatted by acetonitrile-n-hexane partitioning for soybean, peanut and corn grits. The residue was cleaned up with a Florisil column and a Bond Elut® SAX cartrigde column. CE and TM were separated on an HPLC column (Inertsil ODS-2) using acetonitrile-water-phosphoric acid (50:50:0.01) as the mobile phase. These compounds were detected at 240nm.The mean recoveries of these compounds added to crops at the level of 0.1ppm were 59-84% (CE) and 54-79%, except for peanut (TM). The detection limits of CE and TM in crops were 0.01ppm.