SEPARATING SOMATOTROPIN (GROWTH HORMONE) MONOMERS BY PRECIPITATION OF OLIGOMERS THROUGH PH MANIPULATION

摘要

A method for purifying and recovering biologically active somatotropin monomers from refold solution following the solubilization and naturation of refractile bodies of host cells produced by recombinant DNA methodology. The purification process is based on the discovery that somatotropin monomers and somatotropin oligomers having overlapping isoelectric points may nevertheless be separated by selective precipitation over a narrow pH range. Host cell residues including proteins, pyrogens and other impurities present in the refold solution are effectively removed in the process. The purified somatotropin monomers recovered from solution after removing precipitated solids are suitable for parenteral application to target animals without further purification.