Coupled techniques based on liquid chromatography and atomic fluorescence detection for arsenic speciation

Arsenic speciation is performed by using coupled techniques with anion and cation exchange columns and atomic fluorescence detection, with UV irradiation and hydride generation as derivatisation steps. The coupling design is described. A new software is developed which provides a dynamic range wide enough to allow the quantification of arsenic species at very different concentration levels each in the same sample. Two chromatographic columns were used in separate analyses, which permits the quantification of six arsenic compounds (arsenate, arsenate, monomethylarsonate (MMA), dimethylarsinate (DMA), arsenocholine (AsChol), arsenobetaine (AsBet)). Instrumental performance is optimised. Detection limits lower than 4 mu g l(-1) and precision lower than 5% RSD are achieved for all the compounds under study. (C) 2000 Elsevier Science B.V. All rights reserved.