Abstract In this study, recombinant Staphylococcus Protein A (rSPA) was immobilized on three different amino-epoxy agaroses: traditional amino-epoxy, butanediol diglycidyl-amino and glycidyl-amino agarose (coded as AE, BDA and GA agarose, respectively), for obtaining affinity adsorbents to bind human immunoglobulin G (hIgG). The effects of the spacer arm microenvironment of the support on the rSPA immobilization were investigated. Compared with the AE agarose, the GA agarose presents ionized amino groups far from the support. Therefore, the rSPA immobilization efficiency of 92 % is slightly higher than that of 88 % on AE agarose due to the weak steric hindrance. Moreover, the BDA agarose exhibited the lowest immobilization efficiency of 58 %, attributing to the existence of hydrophobic butylidene groups on the BDA agarose. Ethanolamine was used as the blocking agent to obtain three affinity adsorbents. The hIgG-binding capacity from the human plasma was determined to be 18.7, 34.7 and 38.7 mg/mL for rSPA-BDA, rSPA-AE and rSPA-GA, respectively. Furthermore, the maximum hIgG-binding capacity was calculated by the Langmuir model of adsorption isotherm to be 25.1, 44.8 and 52.2 mg/mL for rSPA-BDA, rSPA-AE and rSPA-GA, respectively. Therefore, the GA agarose bears the optimal spacer arm microenvironment for preparing the rSPA adsorbent with high hIgG-binding capacity.

中文翻译：

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用于将重组蛋白 A 固定在异功能氨基-环氧琼脂糖载体上的最佳间隔臂微环境

摘要 在本研究中，重组葡萄球菌蛋白 A (rSPA) 被固定在三种不同的氨基-环氧琼脂糖上：传统的氨基-环氧、丁二醇二缩水甘油-氨基和缩水甘油-氨基琼脂糖（分别编码为 AE、BDA 和 GA 琼脂糖），用于获得亲和吸附剂以结合人免疫球蛋白 G (hIgG)。研究了支持物的间隔臂微环境对rSPA固定的影响。与AE琼脂糖相比，GA琼脂糖呈现远离支持物的电离氨基。因此，由于空间位阻较弱，92% 的 rSPA 固定效率略高于 AE 琼脂糖的 88%。此外，BDA 琼脂糖的固定效率最低，为 58%，这归因于 BDA 琼脂糖上存在疏水性丁叉基。以乙醇胺为封闭剂，得到三种亲和吸附剂。对于 rSPA-BDA、rSPA-AE 和 rSPA-GA，来自人血浆的 hIgG 结合能力经测定分别为 18.7、34.7 和 38.7 mg/mL。此外，通过吸附等温线的朗缪尔模型计算出的最大 hIgG 结合能力分别为 25.1、44.8 和 52.2 mg/mL，对于 rSPA-BDA、rSPA-AE 和 rSPA-GA。因此，GA琼脂糖具有制备具有高hIgG结合能力的rSPA吸附剂的最佳间隔臂微环境。rSPA-BDA、rSPA-AE和rSPA-GA通过吸附等温线的Langmuir模型计算的最大hIgG结合能力分别为25.1、44.8和52.2mg/mL。因此，GA琼脂糖具有制备具有高hIgG结合能力的rSPA吸附剂的最佳间隔臂微环境。rSPA-BDA、rSPA-AE和rSPA-GA通过吸附等温线的Langmuir模型计算的最大hIgG结合能力分别为25.1、44.8和52.2mg/mL。因此，GA琼脂糖具有制备具有高hIgG结合能力的rSPA吸附剂的最佳间隔臂微环境。