Development of a rapid, specific fluorescence polarization immunoassay for the herbicide chlorsulfuron

A strategy for design of a derivative of chlorsulfuron, which mimics half of the herbicide molecule, was proposed. The 1-[(2-chloro)phenylsulfonyl]monoamidosuccinic acid was synthesized as a derivative of chlorsulfuron for conjugation to carrier proteins. Rabbits were immunized and the resulting polyclonal antibodies were assessed by the fluorescence polarization technique. The antibodies were highly specific to chlorsulfuron. Cross-reactivity to the structurally similar sulfonylurea and urea herbicides chlorbromuron, amidosulfuron, chlortoluron, isoproturon, diuron and linuron was less than 0.1%. A rapid fluorescence polarization immunoassay (FPIA) for chlorsulfuron detection in water samples was developed and optimized. The detection limit of chlorsulfuron in 50 μl of sample was 10 ng ml⁻¹. Total time for the measurement of 10 samples is 7 min. The proposed FPIA is suitable for rapid testing for pesticide contamination where the highest sensitivity is not critical or in combination with pre-concentration techniques.