PREPARATION AND CHARACTERIZATION OF NOVEL MAGNETITE-COATED ION-EXCHANGE PARTICLES

Magnetite was incorporated into ion-exchange gel particles in two different modes. By a conventional procedure, magnetite could be dispersed throughout the particles; in addition, a novel method was discovered which led to a porous layer of magnetite coating the particles. Magnetite-coated particles have ion-exchange capacities that are virtually identical to the capacities of untreated particles, for the adsorption of a small (12 kDa) protein. Kinetics of protein binding are somewhat retarded by diffusion through the coating. These magnetic particles were designed for use in magnetically stabilized fluidized beds; induced magnetic interactions were found to be much stronger between magnetite-coated particles than between dispersed magnetite particles.