Abstract: A high performance liquid chromatography-atomic fluorescence spectrometry (HPLC-AFS) method was developed for the determination of methylmercury in aquatic products. Samples were extracted with a mixture of vitriol, potassium chloride and hydrochloric acid. Then the extract was cleaned up on an SPE column, diluted with the HPLC mobile phase and filtrated through a 0.45 μm pore size membrane prior to HPLC-AFS analysis. The quantification of methylmercury was carried out using the external standard method. Good linearity between chromatographic peak area and methylmercury concentration ranging from 2 to 50μg/L was found (R2＝0.9995). Average recoveries for methylmercury in different blank aquatic products spiked at 20, 200 ,1000μg/kg were 80.2%－87.1% with relative standard deviations (RSD) between 3.4% and 6.8%. The method exhibited a detection limit of 20μg/kg. The method had the advantages of simplicity and little matrix interference, and meanwhile its precision and accuracy could meet the requirements for the analysis of methylmercury in aquatic products.

Key words: methylmercury, aquatic product, HPLC-AFS