RAPID ONLINE PRECOLUMN HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF BENOMYL, CARBENDAZIM AND ALDICARB SPECIES IN DRINKING-WATER

A reversed-phase high-performance liquid chromatographic (HPLC) method has been developed for the determination of trace concentrations of benomyl, carbendazim, aldicarb, aldicarb sulphoxide and aldicarb sulphone in drinking water. A 10-ml sample of water is passed through a 3-cm precolumn, packed with 5-mu-m C8 sorbent, at a flow-rate of 5 ml/min. The HPLC system is then switched to an acetonitrile-water gradient elution program. The preconcentrated analytes are eluted from, and separated by, the 3-cm C8 precolumn and determined by UV absorption. The total analytical time is 25 min. The lowest detectable concentrations are in the range of 2.5 . 10(-9) - 11.0 . 10(-9) g/ml for the five analytes investigated with 10 ml of sample.