Evaluation of biosorption and bioaccumulation capacity of cyanobacteria Arthrospira (Spirulina) Platensis for radionuclides

Bioaccumulation and biosorption of ¹³⁷Cs, ²³³U, ²³⁹Pu, ²⁴¹Am, ⁹⁰Sr and ²³⁷Np 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 ²³⁹Pu, ²⁴¹Am, and ⁹⁰Sr in both media, while the uptake of ²³³U was significantly enhanced in the presence of polyphosphate ions. In biosorption experiments, the biomass also showed high sorption capacity for ²³⁹Pu, ²⁴¹Am, and ⁹⁰Sr and low for ²³³U. The amount of ¹³⁷Cs 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. (author)