THEORETICAL-STUDY OF THE ION-EXCHANGE PREPARATIVE CHROMATOGRAPHY OF A 2-PROTEIN MIXTURE

Preparative ion-exchange chromatography of a two-protein mixture is theoretically considered by the use of numerical simulations. The mathematical model is a combination of the semi-ideal model for the chromatographic process, with the stoichiometric displacement model for the basic interactions between proteins and the stationary phase. A study of the selectivity of the adsorption, which appears to be dependent on the loading of the column, makes possible a better understanding of the chromatograms obtained with either isocratic or gradient elution. Special stress is been laid on the effect of overloading the column by pointing out displacement effects between proteins. The influence of important adsorption parameters, such as the characteristic charge or maximum loading capacity, was investigated by considering criteria of production rate, recovery yield and enrichment of products.