Study of modification of magnetically labeled yeasts Saccharomyces cerevisiae for copper cations Cu2+ removal

Research of biosorption and search for the cheapest and effective biosorbents of heavy metals are important for wastewater treatment, recovery and allocation of precious metals. Biosorbent artificially provided with magnetic properties quickly and efficiently can be removed from the workspace. Magnetically labeled biosorbent obtained by multi-vortical MHD stirring of yeast S. cerevisiae with nanoscale magnetic labels is able to remove from solutions a wide range of metals, and is the subject of the study. Sorption properties of cell walls in the case of passive biosorption are dependent from represented on its surface functional groups such as carboxyl and amino groups. Quantitative analysis of the contribution of functional groups, lipids and proteins in sorption capacity of magnetically labeled cells of interest for understanding the sorption of metal cations, interactions of particles of magnetite with cell wall and sorption of metal cations by immobilized magnetite. There is a need to detect how many functional groups are blocked by magnetite during multi-vortical MHD stirring. To solve this problem it is prompted to investigate and analyze the sorption capacity of magnetically labeled yeast by modifying the surface of biosorbent by extraction or blocking in terms of biosorption by functional groups. The results showed that the carboxyl groups, and after them the amino group of the cell wall of native and magnetically labeled yeasts have the greatest contribution to the sorption of copper cations. Magnetic labels interact with −COOH groups and block them − about 15 % of the cell wall components extracted using NaOH. At the same time 1 % by weight of magnetite provides biosorbent equivalent amount of copper cations binding sites on the surface of cells, which in turn leads to the same sorption capacity of native and magnetically labeled yeasts.