【摘要】 针对传统大孔聚合物离子交换层析介质比表面积小而导致蛋白吸附容量低的问题，提出了一种基于“Grafting to”法的新型制备方法来提高蛋白吸附容量.以过硫酸铵为引发剂，引发甲基丙烯酸2-氨基乙酯（2-AM）和N,N-二甲胺基丙基丙烯酰胺（DMAPAA）两种单体共聚，获得带有伯胺基团的预聚物，通过调节2-AM和DMAPAA的摩尔比，控制所得预聚物pDMAPAA的平均聚合度范围为2～10.将该预聚物接枝到大孔聚丙烯酸酯类微球表面，制备了弱阴离子交换层析介质.通过对偶联条件进行优化确定最佳制备条件，并以牛血清白蛋白（BSA）为模型蛋白，探究了不同配基密度以及不同链长的接枝型介质对蛋白静态吸附容量（SBC）的影响规律、不同链长介质的吸附动力学及离子强度对不同配基密度的介质吸附行为的影响.结果表明，接枝链长增加（2～10单元），介质的离子交换容量（IC）和SBC显著提升，平衡吸附容量（q_e）从130.9 mg/mL增加至196.5 mg/mL，但准二级吸附速率常数（k₂）减小；配基密度升高，使SBC从（95.6±2） mg/mL增加至（174.0±3） mg/mL；盐浓度升高（0～0.25 mg/mL），导致SBC下降，较高配基密度的介质表现出更强的盐耐受性.更多还原

【Abstract】 The low protein adsorption capacity is caused by the low specific surface area of traditional macroporous polymer-based ion exchange chromatography media. A novel preparation method based on a "grafting to" strategy was proposed to enhance the protein adsorption capacity in this study. A pre-polymer containing primary amine groups was synthesized by copolymerizing two monomers, 2-aminoethyl methacrylate（2-AM） and N,N-dimethylaminopropylacrylamide（DMAPAA）, using ammonium persulfate as the initiator. The average degree of polymerization of the resulting pre-polymer, pDMAPAA, was controlled between 2 and 10 by adjusting the molar ratio of 2-AM to DMAPAA. This pre-polymer was then grafted onto the surface of macroporous polyacrylate microspheres to fabricate a weak anion exchange chromatography medium. The optimal preparation conditions were determined by optimizing the coupling parameters. Using bovine serum albumin（BSA） as a model protein, the effects of ligand density and grafted chain length on the static binding capacity（SBC）, the adsorption kinetics of media with different chain lengths, and the influence of ionic strength on adsorption behavior at different ligand densities were investigated. The results showed that increasing the grafted chain length（2—10 units） significantly enhanced the ion exchange capacity（IC） and SBC of the media. The equilibrium adsorption capacity（q_e） increased from 130.9 mg/mL to 196.5 mg/mL, while the pseudo-second-order adsorption rate constant（k₂） decreased. A higher ligand density increased the SBC from（95.6±2） mg/mL to（174.0±3） mg/mL. Increasing the salt concentration（0—0.25 mol/L） leded to a decrease in SBC, with media of higher ligand density exhibiting stronger salt tolerance. This study provides a valuable reference for the controlled preparation and application of high-performance weak anion exchange chromatography media.更多还原