MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Langmuir. 2012 Sep 25;28(38):13616-23. doi: 10.1021/la302389e. Epub 2012 Sep 14.
The interactions between glycopolymer brushes and lectin are very important for the development of affinity membrane chromatography in protein separation. Here, we report the combination of surface-initiated atom transfer radical polymerization (SI-ATRP) and surface plasmon resonance (SPR) to investigate the relationship between the structure of glycopolymer brushes and the affinity adsorption of lectin. The glycopolymer brushes were fabricated from self-assembly of 11-mercapto-1-undecanol (MUD)/1-undecanethiol (UDT) mixture, immobilization of ATRP initiators, and then SI-ATRP of 2-lactobionamidoethyl methacrylate (LAMA). Brush thickness and grafting density were adjusted by controlling polymerization time and thiol ratio in MUD/UDT mixture, respectively. Sugar epitope density was also controlled through copolymerization of 2-hydroxylethyl methacrylate (HEMA) with LAMA. Ricinus communis agglutinin (RCA(120)), one kind of lectin that can bind galactose specifically, was chosen to study the effects of brush architectures on lectin adsorption. SPR results indicate not only the thickness but also the grafting density and the epitope density of glycopolymer brushes can achieve the best performance of sugar cluster effect in affinity adsorption of lectin. In addition, the mass transport effect is crucial in the adsorption process. We propose that it is important to keep the balance between the sugar cluster effect and the mass transport effect in the preparation of high-performance affinity membrane chromatography.
糖聚合物刷与凝集素之间的相互作用对于蛋白质分离的亲和膜色谱的发展非常重要。在这里，我们报道了表面引发原子转移自由基聚合（SI-ATRP）和表面等离子体共振（SPR）的结合，以研究糖聚合物刷的结构与凝集素亲和吸附之间的关系。糖聚合物刷是通过 11-巯基-1-十一醇（MUD）/1-十一硫醇（UDT）混合物的自组装、ATRP 引发剂的固定化以及 2-乳糖酰基乙基甲基丙烯酸酯（LAMA）的 SI-ATRP 制备的。通过控制聚合时间和 MUD/UDT 混合物中的硫醇比分别调节刷的厚度和接枝密度。还通过 2-羟乙基甲基丙烯酸酯（HEMA）与 LAMA 的共聚来控制糖基元密度。蓖麻凝集素（RCA（120））是一种可以特异性结合半乳糖的凝集素，被选择来研究刷结构对凝集素吸附的影响。SPR 结果表明，不仅刷的厚度，而且接枝密度和糖基元密度都可以在凝集素的亲和吸附中达到最佳的糖簇效应性能。此外，质量传递效应在吸附过程中至关重要。我们提出，在制备高性能亲和膜色谱时，保持糖簇效应和质量传递效应之间的平衡非常重要。
