Patent ID: 7947813
Filing Date: 2011-05-24
Classification: C07K

Abstract:
1. A method of purifying antibodies comprising: (a) adjusting the acidity or salt concentration of a mixture containing an antibody wherein the antibody is derived from a harvested cell culture fluid; (b) adding a negatively charged polyelectrolyte selected from polyvinylsulfonic acid, polyvinylsulfonate, and polystyrenesulfonic acid, a molecular weight of 1200 to 1,100,000 Da, and a concentration between 0.01% to 1.0% weight/volume in the mixture containing the antibody, whereby a protein-polyelectrolyte precipitate is formed; (c) separating the protein-polyelectrolyte precipitate from impurities selected from protein aggregates, protein fragments, host cell proteins, insulin, gentamicin, DNA, and leached protein A; (d) isolating the protein-polyelectrolyte precipitate; (e) resuspending the protein-polyelectrolyte precipitate in an aqueous solution; and (f) separating the polyelectrolyte from the purified antibody by anion-exchange chromatography of the resuspended protein-polyelectrolyte precipitate.