title: Improved purification of immunoglobulin G from plasma by mixed-mode chromatography.
abstract: Efficient loading of immunoglobulin G in mixed-mode chromatography is often a serious bottleneck in the chromatographic purification of immunoglobulin G. In this work, a mixed-mode ligand, 4-(1H-imidazol-1-yl) aniline, was coupled to Sepharose Fast Flow to fabricate AN SepFF adsorbents with ligand densities of 15-64 mmol/L, and the chromatographic performances of these adsorbents were thoroughly investigated to identify a feasible approach to improve immunoglobulin G purification. The results indicate that a critical ligand density exists for immunoglobulin G on the AN SepFF adsorbents. Above the critical ligand density, the adsorbents showed superior selectivity to immunoglobulin G at high salt concentrations, and also exhibited much higher dynamic binding capacities. For immunoglobulin G purification, both the yield and binding capacity increased with adsorbent ligand density along with a decrease in purity. It is difficult to improve the binding capacity, purity, and yield of immunoglobulin G simultaneously in AN SepFF chromatography. By using tandem AN SepFF chromatography, a threefold increase in binding capacity as well as high purity and yield of immunoglobulin G were achieved. Therefore, the tandem chromatography demonstrates that AN SepFF adsorbent is a practical and feasible alternative to MEP HyperCel adsorbents for immunoglobulin G purification.
authors.affiliation: Department of Biochemical Engineering, Key Laboratory of Systems Bioengineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Chai
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
authors.forename: Xiao-Ning
authors.initials: XN
authors.lastname: Wang
authors.forename: Qing-Hong
authors.initials: QH
authors.lastname: Shi
mesh_terms: D000327:Adsorption; D000818:Animals; D002845:Chromatography / Q000379:methods*; D007074:Immunoglobulin G / Q000302:isolation & purification*; D010949:Plasma / Q000737:chemistry*; D011817:Rabbits
chemical_list: D007074:Immunoglobulin G
keywords: Immunoglobulin G; Ligand density; Mixed-mode adsorbent; Plasma purification; Tandem chromatography