title: Structural and performance characteristics of representative anion exchange resins used for weak partitioning chromatography.
abstract: Weak partitioning chromatography (WPC) has been proposed for the purification of monoclonal antibodies using an anion exchange (AEX) resin to simultaneously remove both acidic and basic protein impurities. Despite potential advantages, the relationship between resin structure and WPC performance has not been evaluated systematically. In this work, we determine the structure of representative AEX resins (Fractogel® EMD TMAE HiCap, Q Sepharose FF, and POROS 50 HQ) using transmission electron microscopy and inverse size exclusion chromatography and characterize protein interactions while operating these resins under WPC conditions using two mAb monomers, a mAb dimer, mAb multimers, and BSA as model products and impurities. We determine the isocratic elution behavior of the weakly bound monomer and dimer species and the adsorptive and mass transfer properties of the strongly bound multimers and BSA by confocal laser scanning microscopy. The results show that for each resin, using the product Kpvalue as guidance, salt, and pH conditions can be found where mAb multimers and BSA are simultaneously removed. Isocratic elution and adsorption mechanisms are, however, different for each resin and for the different components. Under WPC conditions, the Fractogel resin exhibited very slow diffusion of both mAb monomer and dimer species but fast adsorption for both mAb multimers and BSA with high capacity for BSA, while the Sepharose resin, because of its small pore size, was unable to effectively remove mAb multimers. The POROS resin was instead able to bind both multimers and BSA effectively, while exhibiting a greater resolution of mAb monomer and dimer species. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:425-434, 2017.
authors.affiliation: Dept. of Chemical Engineering, University of Virginia, Charlottesville, VA.
authors.forename: Shaojie
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Pfizer, Andover, MA.
authors.forename: Tim
authors.initials: T
authors.lastname: Iskra
authors.affiliation: Pfizer, Andover, MA.
authors.forename: William
authors.initials: W
authors.lastname: Daniels
authors.affiliation: Pfizer, Andover, MA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Salm
authors.affiliation: Pfizer, Andover, MA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Gallo
authors.affiliation: Pfizer, Andover, MA.
authors.forename: Ranga
authors.initials: R
authors.lastname: Godavarti
authors.affiliation: Dept. of Chemical Engineering, University of Virginia, Charlottesville, VA.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Carta
mesh_terms: D000837:Anion Exchange Resins / Q000737:chemistry*; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000302:isolation & purification*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D004058:Diffusion; D008422:Materials Testing; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000837:Anion Exchange Resins; D000911:Antibodies, Monoclonal
keywords: anion exchange chromatography mAb purification; resin structure; transport mechanisms; weak partitioning chromatography