Evaluation of biosorption and bioaccumulation capacity of cyanobacteria Arthrospira (spirulina) platensis for radionuclides

Bioaccumulation and biosorption of Cs-137, U-233, Pu-239, Am-241, Sr-90 and Np-237 by Arthrospira platensis CNMN-CB-02 biomass were investigated. Bioaccumulation experiments were performed in EDTA-free Zarrouk cultivation medium and in the medium with the addition of sodium polyphosphate. Arthrospira platensis CNMN-CB-02 biomass showed high uptake capacity for Pu-239, Am-241, and Sr-90 in both media, while the uptake of U-233 was significantly enhanced in the presence of polyphosphate ions. In biosorption experiments, the biomass also showed high sorption capacity for Pu-239, Am-241, and Sr-90 and low for U-233. The amount of Cs-137 removed from the solution by living and dry biomass was almost the same. The desorption studies revealed that A. platensis CNMN-CB-02 biomass can be reused for biosorption and showed a high strength of radionuclide binding to phosphorylated biomass. A. platensis CNMN-CB-02 biomass can be considered a good candidate for radionuclide removal from salt and alkaline solutions and in in situ bioremediation strategies.