PREPARATION OF A POROUS MICROPARTICULATE ANION-EXCHANGE CHROMATOGRAPHY SUPPORT FOR PROTEINS

A hydrophilic, durable anion-exchange material has been developed for high- performance liquid chromatography of proteins. Polyethyleneimine and simpler amines are adsorbed to porous, microparticulate silicas so strongly that the adsorbed coatings may be crosslinked into a stable layer by a wide variety of reagents in organic solution. Epoxy resins, alkyl bromides, and nitro alcohols are the best cross- linkers. The resulting pellicular coating is more stable in aqueous media than the underlying silica. Porous glass, alumina, and titania can also be coated in this manner. The materials are quite reproducible and of high ion-exchange capacity: up to 2.7 mequiv./g. Columns of polyethyleneimine-coated silica resolve proteins quickly and efficiently with excellent recoveries of enzyme activity. Nucleotides are also well resolved. Efficiency does not change during a column's lifetime. © 1979.