| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1202052 | Journal of Chromatography A | 2012 | 9 Pages |
We compare the rates of adsorption of two monoclonal antibodies (mAbs) with different adsorption properties on the cation exchangers UNOsphere™ S and Nuvia™ S. The former contains large open pores while the latter is based on a backbone matrix similar to UNOsphere™ S but also contains grafted charged polymers. Both single component and two-component adsorption are considered. Adsorption capacity and rates are much higher for Nuvia™ S indicating that protein interactions with the charged grafted polymers facilitate both binding and diffusional transport. Intraparticle concentration profiles obtained by confocal microscopy show sharp fronts for UNOsphere™ S but diffuse profiles for Nuvia™ S. Transport is thus controlled by pore diffusion for UNOsphere™ S but is described by a single file diffusion (SFD) mechanism for Nuvia™ S. As a result, single and two-component adsorption occur at similar rates for UNOsphere™ S independent of the direction for transport. For Nuvia™ S, however, transport is very fast for single or two-component co-adsorption but very slow when counter diffusion of the two mAbs takes place within the particles. The transport models developed in this work allow a prediction of separation performance for overloaded conditions typical of process scale applications.
► Single and multiple mAbs adsorption in macroporous resins is pore diffusion controlled. ► Single and multiple mAbs adsorption in grafted resins is solid diffusion controlled. ► Adsorption rates depend on composition for polymer-grafted resins. ► Single file diffusion model predicts adsorption kinetics in grafted resins.
