Media For Membrane Ion Exchange Chromatography Based On Polymeric Primary Amines, Sorption Device Containing That Media, And Chromatography Scheme And Purification Method Using The Same

Abstract

Media and devices, such as anion exchangers including such media, wherein the media is a membrane having a surface coated with a polymer such as a polyallylamine. The resulting membrane offers stronger binding of protein impurities and superior removal of host cell proteins from biological samples than conventional ligands based on quaternary ammonium salts, including trimethylammonium ligands. Also described is a chromatography scheme and method for purifying monoclonal antibodies, wherein the anion exchange sorber is placed downstream of an affinity column (e.g., Protein A or Protein G) and optionally one or more polishing devices such as cationic exchange columns. Little or no dilution of the cation exchanger pool (or affinity column exchange pool where no cation exchanger is used) is necessary to lower the conductivity of the sample. The sorber functions well to strongly bind host cell proteins and other impurities in biological samples even at high conductivities and pH.

1 . A method of manufacturing an adsorber membrane, comprising providing a substrate having a first external side and a second external side, both sides being porous, and a porous thickness between them; substantially covering said substrate and said first and second external surfaces with a sorptive material comprising a crosslinked polymer having attached primary amine groups; and heating the resulting substrate to a temperature of from about 25° C. to about 120° C. 
     
     
         2 . The method of  claim 1 , wherein said temperature is from about 85° C. to about 100° C. 
     
     
         3 . The method of  claim 1 , further comprising treating the resulting membrane with acid, and subjecting the acid-treated membrane to gamma irradiation. 
     
     
         4 . The method of  claim 3 , wherein said acid is selected from the group consisting of hydrochloric, hydrobromic, sulfamic, methansulfonic, trichloroacetic, and trifluoroacetic acid. 
     
     
         5 . The method of  claim 3 , wherein said acid is sulfamic acid.