Ion chromatography-inductively coupled plasma mass spectrometry determination of arsenic species in marine samples

摘要

Arsenic speciation analysis in marine samples was performed using ion chromatography (IC) with inductively coupled plasma mass spectrometry (ICP-MS) detection.The separation of eight arsenic species,viz.arsenite,monomethyl arsonic acid,dimethylarsinic acid,arsenate,arsenobetaine,tetramethylarsine oxide,arsenocholine and tetramethylarsonium ion was achieved on a Dionex AS4A (weaker anion exchange column) by using a nitric acid pH gradient eluent (pH 3.3 to 1.3).The entire separation was accomplished in 12 min.The detection limits for the eight arsenic species by IC-ICP-MS were in the range 0.03-1.6 mug l~(-1),based on 3sigma of the blank response (n = 6).The repeatability and day-to-day reproducibility were calculated to be less than 10% (residual standard deviation) for all eight species.The method was validated by analyzing a certified reference material (DORM-2,dogfish muscle) and then successfully applied to several marine samples,e.g.oyster,fish muscle,shrimp and marine algae.The low power microwave digestion was employed for the extraction of arsenic from seafood products.