Determination of arsenic species and arsenosugars in marine samples by HPLC-ICP-MS

Arsenic-speciation analysis in marine samples was performed by high-pressure liquid chromatography (HPLC) with ICP-MS detection. Separation of eight arsenic species-As-III, MMA, DMA, As-V, AB, TMAO, AC and TeMAs+-was achieved on a C-18 column with isocratic elution (pH 3.0), under which conditions As-III and MMA co-eluted. The entire separation was accomplished in 15 min. The HPLC-ICP-MS detection limits for the eight arsenic species were in the range-0.03-0.23 mu g L-1 based on 3 sigma for the blank response (n = 5). The precision was calculated to be 2.4-8.0% (RSD) for the eight species. The method was successfully applied to several marine samples, e.g. oysters, fish, shrimps, and marine algae. Low-power microwave digestion was employed for extraction of arsenic from seafood products; ultrasonic extraction was employed for the extraction of arsenic from seaweeds. Separation of arsenosugars was achieved on an anion-exchange column. Concentrations of arsenosugars 2, 3, and 4 in marine algae were in the range 0.18-9.59 mu g g(-1).