METAL-ION CONCENTRATION, TIME, AND PH-DEPENDENCE OF METAL-ION BINDING TO A TRANSFERRIN METALLOPROTEIN AFFINITY-CHROMATOGRAPHY (MAMC) MATRIX

The adsorption of transition metal, lanthanide, and actinide ions to ovotransferrin (conalbumin) immobilized to sepharose (via the cyanogen bromide method) has been examined. Adsorption of ions as a function of time and adsorption isotherms at pH 8 have been determined and analyzed using the Freundlich model. Distribution coefficients between the pH values 2 and 9 have been measured. The results indicate that immobilization of the protein has little effect on its interactions with metal ions compared with the protein in solution, an important prerequisite for use of this matrix in metalloprotein affinity metal chromatography (MAMC).