Void exclusion of antibodies by grafted-ligand porous particle anion exchangers

► A new variant of anion exchange chromatography is described. ► IgG is excluded to the void volume from pH 3-10 and 0-4 M NaCl. ► Exclusion depends on a variable size exclusion effect mediated by grafted ligands. ► Most host cell proteins follow typical pH and salt trends for anion exchange. ► Greater than 99% reduction of all major contaminants is achieved in a single step.