FLUOROMETRIC-DETERMINATION OF AMINOCARB AND MEXACARBATE AND SOME OF THEIR METABOLITES BY LIQUID-CHROMATOGRAPHY - INFLUENCE OF STRUCTURAL FACTORS ON FLUORESCENCE INTENSITY

A direct and sensitive high performance liquid chromatographic method with fluorescence detection is reported to identify aminocarb and mexa carbate and some of their metabolites. The observed detection limits w ere compared by linldng the Liquid chromatograph to a variable wavelen gth UV detector. The separation system consisted of an RP-8 OS (10 mu m) 20 cm x 4.6 mm I.D. column and acetonitrile-phosphate (pH 7.2) buff er. The excitation and emission wavelengths of the fluorescence detect or were set respectively at 200 and 370 nm. The UV detector was set at 242 and 200 nm for aminocarb and mexacarbate, respectively. The sensi tivity in fluorescence detection was not superior to UV method because of the influence of substituents on the aryl ring on fluorescence int ensity. Both methods were found to be adequate for the determination o f most of the analytes from natural water at nanogram levels after nec essary extraction and cleanup procedures.