Abstract
The interaction of radiocobalt with glycine, alanine or aspartic acid dissolved in seawater was investigated under laboratory conditions by means of adsorption on Chelex 100 solvent extraction with dithizone or gel filtration chromatography. The results also were compared with those in freshly prepared or stored culture filtrates of chlorella, fishpond and offshore seawaters in which ionic radiocobalt was spiked, respectively. The distribution coefficients for Co in Chelex 100 and the extraction rates (%) of Co with dithizone in carbon tetrachloride decreased more greatly with time in the presence of the amino acids than in the control. The inhibitory effect of glycin on the adsorption of Co on the Chelex 100 was smaller than that of alanine or aspartic acid. In the fishpond and offshore seawaters or freshly prepared chlorella culture filtrate, the distribution coefficients for Co in Chelex 100 were somewhat greater than in the control, while no significant difference was observed in dithizone extraction. The results of Sephadex G-10 gel filtration chromatography for Co showed that the higher molecular species of Co associated with the amino acids occurred after several days ageing and then increased together with decreasing in the lower molecular species.