Modeling of bispecific antibody elution in mixed‐mode cation‐exchange chromatography

• Published in: Journal of separation science Vol. 40; no. 18; pp. 3632 - 3645
• Main Authors: Lee, Yi Feng, Kluters, Simon, Hillmann, Mirjam, Hirschheydt, Thomas, Frech, Christian
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.09.2017
• Subjects: Antibodies, Bispecific - isolation & purification; bispecific antibody; Cation exchanging; Cations; Chromatography; Chromatography, Ion Exchange; Elution; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Ions; linear pH gradient elution; Mathematical models; mechanistic modeling; mixed‐mode chromatography; Polymers; Proteins; Resins; Salts; Selectivity; bispecific antibody; mixed-mode chromatography; mechanistic modeling; linear pH gradient elution
• ISSN: 1615-9306; 1615-9314
• DOI: 10.1002/jssc.201700313

The increasing demand for cost‐efficient manufacturing of biopharmaceuticals has been the main driving force for the development of novel chromatography resins, which resulted in the development of multimodal or mixed‐mode chromatographic resins. Most of them combine electrostatic and hydrophobic functionalities and are designed to deliver unique selectivity and increased binding capacities also at increased ionic strength. However, the mechanism of the protein–resin interaction in mixed‐mode chromatography is still not fully understood. The performance of protein separations in mixed‐mode chromatography is consequently difficult to predict. In this work, we present a model combining both salt and pH dependence to characterize and to predict protein retention in mixed‐mode chromatography. The model parameters are determined based on simple linear pH gradient elution experiments at different ionic strengths and they are directly transferable for the prediction of salt‐induced elution at fixed pH. Validity of the model is demonstrated for a bispecific antibody and its product‐related impurities.