Protein purification

Abstract

A method for purifying proteins by Protein A chromatography is described which comprises the steps of: (a) adsorbing the protein to Protein A immobilized on a solid phase comprising silica or glass; (b) removing contaminants bound to the solid phase by washing the solid phase with a hydrophobic electrolyte solvent; and (c) recovering the protein from the solid phase.

1 . A method for purifying a protein, which comprises a C H 2/C H 3 region, from a contaminated solution thereof by Protein A chromatography comprising: 
 (a) adsorbing the protein to Protein A immobilized on a solid phase comprising silica or glass;    (b) removing contaminants bound to the solid phase by washing the solid phase with a hydrophobic electrolyte solvent; and    (c) recovering the protein from the solid phase.    
     
     
         2 . The method of  claim 1  wherein the protein is an antibody.  
     
     
         3 . The method of  claim 1  wherein the protein is an immunoadhesin.  
     
     
         4 . The method of  claim 1  wherein the hydrophobic electrolyte solvent comprises tetramethylammonium chloride (TMAC).  
     
     
         5 . The method of  claim 1  wherein the hydrophobic electrolyte solvent comprises tetraethylammonium chloride (TEAC).  
     
     
         6 . The method of  claim 1  wherein the solid phase is a controlled pore glass column.  
     
     
         7 . The method of  claim 1  wherein the solid phase is a silicic acid column.  
     
     
         8 . The method of  claim 1  wherein the contaminants are Chinese Hamster Ovary Proteins (CHOP).  
     
     
         9 . The method of  claim 1  wherein the concentration of the hydrophobic electrolyte in the hydrophobic electrolyte solvent is in the range from about 0.1 to about 1.0 M.  
     
     
         10 . The method of  claim 1  wherein the pH of the hydrophobic electrolyte solvent is in the range from about 4 to about 8.  
     
     
         11 . The method of  claim 1  wherein step (c) comprises eluting the protein using an elution buffer having a pH in the range from about 2.0 to about 5.0.