Automated determination of Vinclozolin at the ppb level in aqueous samplesby a combination of microporous membrane liquid-liquid extraction and adsorption chromatography

An automated system with microporous membrane liquid-liquid extraction (MML LE) combined with HPLC has been designed for the determination of Vinclozol in in aqueous matrices. In MMLLE a porous hydrophobic membrane separates an aqueous phase from an organic phase. The pores are filled with the organic solvent. In this work, MMLLE was performed in a flow system and coupled on -line to normal phase HPLC. The performance of the system was evaluated wit h respect to enrichment when processing large sample volumes. Enrichment fa ctors of 118 times were obtained and the limit of detection was around 1 ng /ml. This technique is an alternative to classical LLE and offers advantage s such as reduced solvent consumption, possibility of automation and avoida nce of emulsion formations. (C) 2000 Elsevier Science B.V. All rights reser ved.