Preparative high-performance liquid chromatography of proteins on an anion exchanger using unfractionated carboxymethyldextran displacers.

It has been previously demonstrated that carboxymethyldextran (CMD) displacers fractionated on an ion-exchange column can be used for the resolution and high capacity displacement chromatography of proteins on high-performance ion-exchange columns. It is shown, in this manuscript, that high resolution and high capacity are obtainable using unfractionated CMD displacers. Up to 25 mg of a mixture of ovalbumin, alpha-lactalbumin, and soy-bean trypsin inhibitor along with many impurities were separated on a 3.3-ml Altex DEAE-5PW column using three unfractionated CMD displacers and a final CMD displacer. A method for removing the displacers from proteins, on a hydrophobic interaction column, is also described.