Monoclonal antibody purification process using protein A

A process for the purification of immunoglobulins which comprises:

• mixing a medium containing immunoglobulins with a buffer solution having a pH in the range of about pH 7.5 to pH 10 and containing a combination of monovalent cations and polybasic anions in a concentration of about 0.6M to 1.75M to provide a buffered immunoglobulin medium;
• contacting said buffered immunoglobulin medium with an immobilized protein A adsorbent to adsorb the immunoglobulins present in said buffered immunoglobulin medium upon said immobilized protein A adsorbent;
• washing the immobilized protein A adsorbent having immunoglobulins adsorbed thereon with said buffer solution;
• contacting said immobilized protein A adsorbent having immunoglobulins adsorbed thereon with a buffer solution having a pH in the range of about pH 3 to pH 6 to remove the adsorbed immunoglobulins from the immobilized protein A adsorbent;
• and
• recovering the removed immunoglobulins in substantially pure form.