自制纤维素金属螯合亲和膜的部分吸附性能及纯化牛血SOD

Partial Adsorption Characteristics of Self-made Cellulose Metal-chelated Affinity Membraneand Its Application for Purification of Bovine SOD from Blood

自制纤维素金属螯合亲和膜,研究亲和膜对金属离子(Cu2+,Ni2+,Fe3+)和蛋白质的吸附性能,建立一种简便实用的纯化SOD的方法.以纤维素滤纸为原料,经交联制成可螯合金属离子的纤维素亲和膜,筛选确定与亲和膜吸附量最大的金属离子,并以卵清蛋白的吸附-解吸实验考查该膜对蛋白质的吸附性能.结果,在Cu2+,Ni2+和Fe3+中,亲和膜对Cu2+的吸附量最大,多次重复实验Cu2+吸附量稳定维持在4.60×10-6mol/cm2左右.Cu2+亲和膜对生理盐水溶卵清蛋白的吸附量高于无离子水溶卵清蛋白,可达113×10-6g/cm2,但蛋白解吸率前者低于后者,表明一定浓度的NaCl有助于亲和膜对蛋白质的吸附,同时也使被吸附的蛋白的解吸率有所降低.吸附-解吸方式(静态法)分离纯化SOD,解吸样品比活达8770 U/mg,纯度为81%;吸附-洗脱方式(动态法)分离纯化SOD,穿柱流出样品比活达12418 U/mg,纯度为85%.自制纤维素亲和膜有较好的吸附性能和纯化效果,重复使用性能良好,制备和纯化过程简便易行,具有广阔应用前景.

To study adsorption characteristics for metal ion（Cu^2＋ , Ni^2＋ , Fe^3＋） and proteins of self-made cellulose metal-chelated affinity membrane, and establish an efficient and convenient method for purifing superoxide dismutase（SOD）, affinity membrane with Cu^2＋ , Ni^2＋ and Fe^3＋ was prepared using cellulose filter paper as a matrix. Adsorption characteristics for proteins of affinity membrane were studied by adsorption-desorption experiments of ovalhumin. The adsorption capacity of affinity membrane for Cu^2＋ was the largest among Cu^2＋ ,Ni^2＋ and Fe^3＋ , and the adsorption capacity kept steadily at about 4.6×10^-6mol/cm^2. The adsorption capacity of Cu^2＋ affinity membrane for ovalbumin dissolved in 9 g/L NaCl was higher than that dissolved in deionized water, and reached 113×10^-6g/cm^2 , but as for protein recovery, the former was lower than the latter. The SOD sample with specific activity of 8770U/mg, purity of 81% was desorbed from affinity membrane by static adsorption-desoption. The liquid that passed through the mem-brane dynamic adsorption-elution was specific activity of 12418 U/mg and purity of 85%.