Protein adsorption onto diethylaminoethyl dextran modified anion exchanger: Effect of ionic strength and column behavior

Abstract

Abstract Our previous studies on bovine serum albumin (BSA) adsorption to diethylaminoethyl dextran (DEAE dextran, DexD, grafting-ligand) and DEAE (D, surface-ligand) modified Sepharose FF resins found that all the grafted resins (FF-DexD and FF-D-DexD) exhibited extremely fast uptake rate (effective diffusivity, De, De/D0 > 1.4), which was six times greater than the ungrafted resins (De/D0 1.1) at the their working/binding IS range. Moreover, the DEAE dextran-FF resin displayed much higher adsorption capacities and De values than commercial ungrafted resin in their working condition. Furthermore, the column results of DEAE dextran-FF resins presented higher dynamic binding capacities than and similar elution ISs with DEAE Sepharose FF to achieve similar (or even higher) recoveries suggest the excellent chromatographic column performance of the DEAE dextran-FF resins. Finally, both high recovery and purity of BSA and γ-globulin could be easily achieved using the typical DEAE dextran-FF column, FF-D60-DexD160, to separate their binary mixtures, by step gradient elution. The research has provided new insights into the practical application of the series of DEAE-dextran grafted resins in protein chromatography and proved their superiority.