On the spirulina platensis: 60Co2+ bioaccumulation system

Radiochemical studies, IR spectrometry and electronic microscopy studies have been made with the purpose of establishing the mechanisms involved in the bioaccumulation of 6 0 Co 2 + on the blue alga Spirulina platensis. By measuring radioactivity, it was determined that - without ionic competition - a one week old culture of Spirulina platensis can retain up to 65% of the 6 0 Co 2 + ions from a slightly radioactive solution. Sodium carbonate is involved in the mechanism of the bioaccumulation of these β+γ-radiocations (phenomenon demonstrated through IR spectrometry). Electronic microscopy studies point that the compounds resulted from the interaction between the exopolysaccharides and 6 0 Co 2 + disperse in the solution. Thus, even though the radiocobalt is completely blocked up in complex compounds, it is not completely retained on the surface and inside of that alga.