DETERMINATION OF HERBICIDES IN SURFACE-WATER BY MEANS OF A SUPPORTED LIQUID MEMBRANE TECHNIQUE AND HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A technique for sample workup and enrichment using a supported liquid membrane (SLM) and high-performance liquid chromatography (HPLC) was u sed for the determination of basic herbicides in spiked lake water. Th e herbicides studied were propazine and simazine as triazine herbicide s, and fenuron, monolinuron and diuron as phenylurea herbicides. The a lkalized sample of water, as the donor solution, comes in contact with the liquid membrane into which analytes are extracted. On the other s ide of the membrane, analyzed compounds are trapped by dissociation in acidic acceptor solution. Enriched and cleaned up herbicides were inj ected into a HPLC system with ultraviolet detection. An increase of co ncentration after SLM extraction was observed only for triazine herbic ides. The detection limit for enrichment of 40 ml of lake water was ab out 0.1 ppb.