title: A predictive approach to correlating protein adsorption isotherms on ion-exchange media.
abstract: The equilibrium adsorption of three small basic proteins was measured on cation exchangers under various solution conditions and was used as the basis for developing a predictive approach for correlating adsorption behavior. A mechanistically based isotherm model is used to model the equilibrium adsorption so as to facilitate isotherm prediction using minimal experimental data. The model explicitly considers the contributions of protein-surface and protein-protein interactions, and decoupling them allows each to be correlated with different experimental measurements. Specifically, protein-surface interactions are related to chromatographic data in the form of the isocratic retention factor (k'), while protein-protein interactions are analyzed on the basis of high-coverage isotherm data on an arbitrary stationary phase. Analysis of experimental data within this framework reveals a high level of consistency. The model is also used to facilitate prediction of adsorption isotherms on other ion-exchange media using isotherms on one adsorbent.
authors.affiliation: Center for Molecular and Engineering Thermodynamics, Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, USA.
authors.forename: Xuankuo
authors.initials: X
authors.lastname: Xu
authors.forename: Abraham M
authors.initials: AM
authors.lastname: Lenhoff
mesh_terms: D000327:Adsorption; D000465:Algorithms; D002021:Buffers; D002411:Cation Exchange Resins / Q000737:chemistry*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D005544:Forecasting; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D012996:Solutions / Q000737:chemistry*; D013499:Surface Properties; D013816:Thermodynamics
chemical_list: D002021:Buffers; D002411:Cation Exchange Resins; D011506:Proteins; D012996:Solutions; D012965:Sodium Chloride