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USGS · 70193470

Separation of selenium species released from Se-exposed algae

John M. Besser·James N. Huckins·Randal C. Clark
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Abstract

We have assessed a fractionation scheme for selenium species that separates Se-containing amino acids and other organoselenium compounds in aqueous samples. We investigated the retention of standard solutions of selenate (Se +6 ), selenite (Se +4 ), and selenomethionine (Se −2 ) by fractionation media (Sephadex A-25 ion-exchange resin, copper-treated Chelex-100 ligand-exchange resin, and activated charcoal) and by several types of membrane filters. The fractionation method successfully isolated Se from the standard solutions into appropriate fractions for radiometric quantitation of 75 Se. However, some filter media retained unacceptably large amounts of selenate and selenite. Mass balance microcosms were inoculated with green algae ( Chlamydomonas "> Chlamydomonas reinhardtii "> reinhardtii ) previously exposed to inorganic 75 Se, and the fractionation scheme was used to examine the release of 75 Se species into water and air. The results of the microcosm exposure indicate that seasonal blooms and crashes of phytoplankton populations may produce increased concentrations of organoselenium species.

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John M. Besser, James N. Huckins, Randal C. Clark. 1994. Separation of selenium species released from Se-exposed algae. https://doi.org/10.1016/0045-6535(94)90045-0

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