Binary protein adsorption on gel-composite ion-exchange media

✍ Scribed by Rebecca Karst Lewus; Giorgio Carta

• Publisher: American Institute of Chemical Engineers
• Year: 1999
• Tongue: English
• Weight: 168 KB
• Volume: 45
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690450308

✦ Synopsis

The adsorption kinetics of mixtures of lysozyme and cytochrome-C on S-HyperD-M, a cation exchanger composed of a rigid macroporous silica matrix whose pores are filled with a functionalized polyacrylamide gel, was characterized. Single-component isotherms were found to follow approximately the steric mass-action law of Brooks and Cramer, and an extension of this model to a binary system was consistent with two-component uptake equilibrium results. Transient adsorption experiments were done to in®estigate the kinetics of sequential and simultaneous adsorption of the two proteins. At low protein concentrations, adsorption is essentially noncompetiti®e, and mass transfer is controlled by the external film resistance. At higher concentrations, equilibrium becomes competiti®e and coupling of the intraparticle diffusion fluxes occurs. A model based on a Maxwell ᎐ Stefan approach, where the dri®ing force for diffusion is expressed in terms of the chemical potential gradient, was in approximate agreement with the experimental results.