Abstract

The bioavailability of therapeutic proteins is improved through PEGylation. This chemical modification involves the production of isomers with different number and site of attached PEG chains, which are difficult to separate efficiently. Their purification with chromatography requires the understanding of the operation and the evaluation of different operational conditions. We applied the General Rate Model (GRM) for modelling the linear salt gradient elution of mono-PEGylated and native lysozyme in Heparin Affinity Chromatography (HAC) considering mass balance equations for proteins in the bulk-fluid phase, in the particle phase and the kinetic adsorption.