5.1.1.17	ammonium sulfate, DE-52, DEAE-Affi-gel blue, Sephadex G-200, calcium phosphate, Mono Q	
5.1.1.17	ammonium sulfate, Sephadex G-200, DEAE-trisacryl	
5.1.1.17	by anion exchange chromatography, purified IPN epimerase is able to act in both orientations, leading in vitro to an equimolecular mixture of isopenicillin N and penicillin N	
5.1.1.17	protamine sulfate, ammonium sulfate, Sephadex G-75, Mono Q