Preliminary studies for the differential-pulse polarographic determination of a new class of herbicides: sulphonylureas

Abstract

The electrochemical behaviour of four sulphonylureas (chlorsulfuron, metsulfuron methyl, DPX-M6316 and chlorimuron ethyl) used as active compounds in commercial herbicides was studied. Methanol-water solutions of the compounds were analysed by differential-pulse polarography. The dependence of peak potentials and peak height on the pH is reported. Detection limits of the order of 10^–8M were obtained, working at a pH of between 2 and 3. Attempts to use a mercury-coated glassy carbon electrode, in view of the possible applications to high-performance liquid chromatography with electrochemical detection, gave unsatisfactory results due to the interference from hydrogen ion reduction.