Porous Adsorptive Or Chromatographic Media

Abstract

A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

The invention claimed is: 
     
         1 . A porous coated composite sheet for adsorption based separations comprising:
 a porous, self-supporting woven or non-woven fabric polyolefin base sheet, coated with one or more porous crosslinked polyallylamine coatings formed on at least a portion of all surfaces of the porous base sheet,   wherein the one or more porous coatings have a void volume fraction of the porous base sheet of at least 1%, and wherein said composite sheet comprises a filter selected from a gridded filter, curricular shaped filter, disc shaped filter, pleated filter, depth filter and combinations thereof.   
     
     
         2 . The composite sheet of  claim 1 , wherein the filter is incorporated into a device selected from a holder, laboratory device, syringe, microtiter plate, filter cartridge, and cartridge. 
     
     
         3 . The composite sheet of  claim 1 , wherein the porous base sheet has a mean flow pore (MFP) rating about 1 micron to 500 microns. 
     
     
         4 . The composite sheet of  claim 1 , wherein the porous base sheet has a pore size about 10 microns to about 300 microns. 
     
     
         5 . The composite sheet of  claim 1 , wherein the porous base sheet has a pore size about 50 microns to about 200 microns. 
     
     
         6 . The composite sheet of  claim 1 , wherein the coating has a thickness about 1 micron to about 100 microns. 
     
     
         7 . The composite sheet of  claim 1 , wherein the coating has a thickness about 2 microns to about 50 microns. 
     
     
         8 . The composite sheet of  claim 1 , wherein the coating further comprises one or more functional groups selected from the group consisting of ion exchange, bioaffinity, hydrophobicity, covalent chromatography, thiophilic interaction, chelation, pi-pi interactions, hydrogen bonding and hydrophilicity. 
     
     
         9 . The composite sheet of  claim 1 , wherein the coating further comprises one or more protein ligands selected from the group consisting of natural protein A, recombinatorily derived protein A, caustic stabilized protein A, natural protein G, recombinatorily derived protein G, and caustic stabilized protein G. 
     
     
         10 . The composite sheet of  claim 1 , wherein the coating further comprises one or more chemical ligands selected from the group consisting of 2-aminobenzimidazole, aminomethylbenzimidazole, mercaptoethylpyridine and mercaptobenzimidazole. 
     
     
         11 . A composite media for adsorption based separations having good convective and diffusional flow characteristics and high dynamic capacity comprising:
 a porous polyolefin sheet of a woven or non-woven fabric having a pore size about 0.1 micron to about 10 microns, and   a porous crosslinked polyallylamine coating on at least a portion of all surfaces of the porous sheet, the coating having a pore size about 1 nanometer to about 200 nanometers, and a thickness about 2 microns to about 20 microns,   wherein the coating occupies about 1% to about 50% of the void volume of the pores of the porous sheet, and wherein composite media comprises a filter, and the filter is incorporated into a device selected from a holder, laboratory device, syringe, microtiter plate, filter cartridge, and cartridge.