Determination of arsenic compounds in reference materials by HPLC-(UV)-HG-AFS

Arsenic compounds were determined in six reference materials of biological origin. None of them has yet been certified for arsenic compounds but some are in the process of certification; for most of these reference materials indicative literature values are available. Eight commonly used arsenic sta ndards were used for quantification using a recently developed hyphenated s peciation system comprising high performance liquid chromatography (HPLC) a nd atomic fluorescence spectrometry (AFS), interfaced via a UV-photoreactor and a hydride generation (HG) unit. Absolute detection limits were ca. 0.2 and 0.4 ng As for separation on anion and cation exchange columns, respect ively. Our results agree well with indicative literature values which were generated by different authors using various separation and detection metho ds. The HPLC-(UV)-HG-AFS system validated in this way is suitable for quant ification of eight arsenic compounds. Moreover, the system is capable of se paration of at least six more compounds in the mentioned reference material s, of which two could be attributed to arsenosugars (OH and phosphodiester form) but due to the lack of standards, quantification was not possible. Fo r accurate and extensive speciation analysis the availability of certified reference materials and standards for arsenic compounds should be promoted. (C) 1999 Elsevier Science B.V. All rights reserved.