Kinetics of uptake of cadmium by Chlorella marina in different media

The kinetics of cadmium binding to living Chlorella marina cells during a short time (a few minutes) has been studied in seawater conditions, being also considered separately the influence of calcium and chloride. Cadmium complexes with surface groups of C. marina cells are labile in terms of differential pulse anodic stripping voltammetry in media (0.01-0.7) M NaNO3 since the complexation reaction is kinetically fast. However, in media 0.7 M NaCl, 0.7 M NaCl + 10(-2) M Ca2- and in synthetic seawater diluted 1:4 or not, the complexes are inert, since kinetics is determined by the rate of exchange with alkaline-earth metals and/or the chloride anion.