Ion-exchange chromatography of proteins on a polyethyleneimine-grafted hydrophilic polymer for high-performance liquid chromatography.

A new, macroporous, synthetic polymer, Hydrophase HP-PEI, having highly hydrophilic surface characteristics enhanced by evenly distributed polyethyleneimine groups on its surface, was evaluated as an high-performance ion-exchange chromatographic packing material for the separation of proteins and nucleotides. A steel column (100 mm x 7.8 mm I.D.) packed with this material produces more than 33,000 plates per m. This base polymer included large proteins, such as thyroglobulin and apoferritin, in a size-exclusion mode. With various proteins it gave high recovery, high resolution and high capacity.