Media for membrane ion exchange chromatography
Media for chromatographic applications, wherein the media is a membrane having a surface coated with a polymer such as a polyethyleneimine. The immobilized polymer coating is modified with a charge-modifying agent to impart quaternary ammonium functionality to the media. The media is well suited for chromatographic purification of virus.
1 . A porous sorptive media comprising a substrate having a first external side and a second external side, both sides being porous, and a porous thickness between them, said substrate being hydrophilic and having a sorptive material substantially covering the solid matrix of the substrate and said first and second external surfaces, said sorptive material comprising a crosslinked polymer having attached quaternary ammonium functionality through a non-polar linker.
2 . The porous sorptive media of claim 1 , wherein said substrate comprises a microporous membrane.
3 . The porous sorptive media of claim 2 , wherein said membrane comprises a polyolefin.
4 . The porous sorptive media of claim 3 , wherein said polyolefin is polyethylene.
5 . The porous sorptive media of claim 1 , wherein said substrate is an ultrahigh molecular weight polyethylene membrane.
6 . The porous coated media of claim 1 , wherein said crosslinked polymer comprises polyethyleneimine.
7 . The porous coated media of claim 1 , wherein said cross-linked polymer is modified with a charge-modifying agent comprising an organic compound having quaternary ammonium groups connected by said non-polar linker to a moiety capable of reacting with said cross-linked polymer.
8 . The porous coated media of claim 7 , wherein said organic compound has the formula Y-Z-N(CH 3 ) 3 + X − , wherein Y is a reactive leaving group, Z is a non-polar aliphatic or aromatic linker, and X is a negatively charged ion of a water-soluble acid.
9 . The porous coated media of claim 8 , wherein Y is a member selected from the group consisting of Br—, Cl—, I—, TsO— and CF 3 SO 3 —, and Z is (CH 2 ) n where n is from 2 to 10.
10 . The porous coated media of claim 6 , wherein the quaternary ammonium functionality is imparted to said polyethyleneimine by 3-bromopropyltrimethyl ammonium bromide.
11 . A method of purifying a virus, comprising passing a solution comprising said virus through a membrane to adsorb said virus, said membrane comprising a substrate having a first external side and a second external side, both sides being porous, and a porous thickness between them, said substrate being hydrophilic and having a sorptive material substantially covering the solid matrix of the substrate and said first and second external surfaces, said sorptive material comprising a crosslinked polymer having quaternary ammonium functionality through a non-polar linker; washing said membrane with buffer; and eluting said virus off said membrane.
12 . The method of claim 11 , wherein said cross-linked polymer is modified with a charge-modifying agent comprising an organic compound having quaternary ammonium groups connected by said non-polar linker to a moiety capable of reacting with said cross-linked polymer.
13 . The method of claim 12 , wherein said organic compound has the formula Y-Z-N(CH 3 ) 3 + X − , wherein Y is a reactive leaving group, Z is a non-polar aliphatic or aromatic linker, and X is a negatively charged ion of a monovalent water-soluble acid.
14 . An anion exchanger comprising porous sorptive media comprising a substrate having a first external side and a second external side, both sides being porous, and a porous thickness between them, said substrate being hydrophilic and having a sorptive material substantially covering the solid matrix of the substrate and said first and second external surfaces, said sorptive material comprising a crosslinked polymer having attached quaternary ammonium functionality through a non-polar linker.