Determination of arsenic species in oyster tissue by microwave-assisted extraction and liquid chromatography-atomic fluorescence detection

A method for the determination of arsenic species in oyster tissue is established. The extraction of arsenic species is carried out by using low-power microwaves. Quantitative extraction is obtained at a power of 40 W, and in 5 min, using the extracting agent methanol/water (I + 1). The measurements are carried out using liquid chromatography-UV irradiation-hydride generation-atomic fluorescence detection (LC-UV-HG-AFS). Three arsenic species were detected in oyster tissue: arsenobetaine (AsBet) (87%), a probable arsenosugar (AsS) (4.9%), and dimethylarsinate (DMA) (4.7%). No influence of the clean-up, the microwave field or the IR drying system on the stability of the arsenic compounds was observed. The extracts can be kept stable up to 3 days at 4 degreesC. The performance of the method is proved on fresh samples, as they are usually analysed in routine laboratories. Copyright (C) 2001 John Wiley & Sons, Ltd.