ChemInform Abstract: Bioaccumulation and Voltammetric Behavior of Gold at Alga-Containing Carbon Paste Electrodes.

ChemInform Abstract

The accumulation and voltammetric behavior of a carbon paste electrode modified with the green alga Chlorella pyrenoidosa, that is suitable for selective measurements of gold, are reported. Gold ions are more strongly bound to this surface modifier than any of the other metal ions tested. Compared with other algae, the Chlorella species has the highest binding capacity for gold. Tetrachloroaurate(III) is bioaccumulated on the electrode surface under open circuit conditions and the electrode is transferred to an electrochemical cell for voltammetric measurements. Regeneration of the surface in a NaCN solution allows the use of a single electrode in multiple analytical determinations. The strength of the method lies in its unique selectivity (based on the biochemical process), rather than its sensitivity. The concept of alga-modified electrodes is of great potential for analytical applications as well as for elucidating metal-microorganism interactions.