DETERMINATION OF BENOMYL RESIDUES IN WATERS BY SOLID-PHASE SPECTROFLUOROMETRY

A sensitive spectrofluorimetric method for the determination of trace amounts of benomyl was developed, based on solid-phase spectrofluorime try. The relative fluorescence intensity of the benomyl fixed on C-18 silica gel was measured directly after packing the gel beads in a 1 mm silica cell, using a solid-phase attachment, The wavelengths of excit ation and emission were 293 and 375 nm, respectively. The applicable c oncentration range was from 0.2 to 20.0 ng ml(-1), with a relative sta ndard deviation of 1.1% and a detection limit of 0.04 ng ml(-1), The m ethod was applied to the determination of benomyl residues in natural waters. Recoveries were 96-103%. The method is more sensitive and sele ctive than other methods described in the literature.