Complementarity of multidimensional HPLC-ICP-MS and electrospray MS-MS for speciation analysis of arsenic in algae

HPLC-ICP-MS using different separation mechanisms: reversed-phase, anion-exchange, cation-exchange, and size-exclusion was revisited and comprehensively evaluated using a set of 14 standards of arsenic species. An analytical protocol based on three-dimensional (sizeexclusion-anion-exchange-reversed-phase) chromatography, capable of isolating individual arsenocompounds from a biological sample, and electrospray tandem mass spectrometry (ES MS-MS), for their identification, was developed. Two minor arsinoylribosides could be detected in addition to As(V) and one major riboside in the algae (Hizikia fusiforme) sample investigated. The other minor species isolated showed different chromatographic behavior than the standards available while the ES MS-MS fragmentation patterns indicated the presence of an arsenoylriboside moiety.