ION-PAIR REVERSED-PHASE LIQUID-CHROMATOGRAPHY WITH FLUOROMETRIC DETECTION OF PESTICIDES

The pesticides asulam, propoxur, coumatetralyl, biphenyl-2-ol and thia bendazole were separated by ion-pair reversed-phase liquid chromatogra phy with fluorescent detection. The mobile phase contained methanol, a cetic acid and sodium cholate as ion-pair reagent. In addition, tetram ethylammonium hydrogensulphate and triethylamine were added to elute t he pesticides. Separations were accomplished in less than 20 min. Inte rferences from nineteen pesticides were studied and recoveries from sy nthetic mixtures ranging from 90 to 110%. Recoveries from spiked apple s and wheat grains ranged from 94 to 105% with relative standard devia tions between 1.4 and 9.2% and detection limits between 0.1 and 1.9 ng .