In the pharmaceutical and biotechnological industry, the downstream processing of fermentation broths normally involves numerous steps for biomass removal and product purication. In the early days of biomolecule purication, the only practical method used for protein separation from complex mixtures was based on protein precipitation by water miscible organic solvents . Alteration of the solvent properties by addition of neutral salts and/or organic solvents leads to precipitation of the macromolecule due to differences in solubility. Alternative processes including adsorption techniques, gel ltration, liquid-phase partitioning, electrophoretic methods, and membrane technologies have lately been developed for protein purication. Adsorption techniques often result in purication steps that give the greatest increase in protein purity. Therefore, they became
widely employed especially when adopted in combination with chromatographic and membrane processes.