Mixed-Mode Expanded-Bed Adsorption for Human Serum Albumin Separation

Mixed-mode chromatography (MMC) is a promising technology for protein separation with high adsorption capacity, good selectivity, salt-tolerance, and facile elution. Expanded bed adsorption (EBA) can capture target proteins directly from bioparticle containing crude feedstock without solid–liquid separation. In this study, MMC and EBA were combined to develop a mixed-mode EBA technique for human serum albumin (HSA) separation. Two mixed-mode EBA resins (using quartz-densified agarose beads and tungsten carbide/agarose composite beads, respectively) with tryptamine as the ligand were prepared (TA-S and TA-T). Static and dynamic adsorption behaviors of HSA were determined under varying conditions and typical adsorption properties of pH dependence and salt-tolerance were found. The performance of the resins in expanded bed was studied, and the dynamic binding capacities at 10% breakthrough (Q10%) of TA-S and TA-T at bed expansion of 1.8 were 27.54 and 18.04 mg/mL settled resin, respectively. Moreover, these ...