ProteinA亲合膜色谱柱的性能及从人血浆中纯化免疫球蛋白的研究

The Property of Protein A Affinity Membrane Cartridge and Purification of IgG from Human Plasma

以木纤维为基质，与甲基丙烯酸环氧丙酯共聚接枝合成了复合膜介质，用复合膜介质制备了ｐｒｏｔｅｉｎＡ亲合膜色谱柱，考察了ｐｒｏｔｅｉｎＡ亲合膜色谱柱液相流动特性和吸附性能。实验证明：流速与亲合膜色谱柱柱压呈线性关系，当流速为３ｍＬ／ｍｉｎ时，柱压为１６０ｋＰａ。免疫球蛋白（ＩｇＧ）浓度和上样速度是影响ｐｒｏｔｅｉｎＡ键合容量的重要因素，对其进行了优化研究。用动态吸附法确定了对人ＩｇＧ动态最大吸附能力可达２１．７ｍｇ／ｇ（干介质）。通过对人血浆中ＩｇＧ的分离纯化考察了ｐｒｏｔｅｉｎＡ亲合膜色谱柱的分离能力，用毛细管电泳对纯化人ＩｇＧ的纯度进行了分析，证明一步纯化ＩｇＧ纯度可达９８％以上。亲合膜色谱柱分离速度快，操作简单，吸附容量满足要求，有望在免疫球蛋白的大规模分离纯化中得到应用。

A new protein A affinity membrane based on composite matrix formed by covalent cross linking of the glycidyl methylacrylate to softwood cellulose fiber was developed. The study focused on the physical properties and adsorption capacity of the affinity membrane cartridge. The results showed that the relationship between flow rate and backpressure was linear. When flow rate was 3 mL/min, backpressure attained 160 kPa. The effects of IgG mass concentration and sampling flow rate on the binding capacity by protein A cartridge were studied for the optimum purification of IgG. A 21. 7 mg/g dry matrix of maximum dynamic binding capacity for IgG was obtained by dynamic adsorption. The cartridge was loaded with human plasma to test its ability to fractionate IgG. The IgG purified from human plasma was analysed by capilary zone electrophoresis (CZE). The results showed that the protein A affinity membrane cartridge had high selectivity for IgG from human plasma. The purity of IgG from human plasma purified by the immobilized protein A membrane cartridge was over 98%. The fast flow property of the membrane cartridge made from such a matrix and its simplicity in operation provide effective means for purifying immunoglobulins on a relatively large scale.