Separation of protein monomers from aggregates by solid weak anion exchange support functionalized with amine moieties

A flow-through process for separating protein monomer from aggregates of that protein in a solution containing both protein monomer and aggregates of that protein, the process includes the steps of 1) contacting the solution at a pH of from 4 to 7 with a weak anion exchange media comprised of multiple primary, secondary and/or tertiary amine functionalization groups whereby the protein monomer flows through the media without binding thereto and the aggregates are retained on the media, and 2) collecting the flow-through as purified protein monomer.