聚乙二醇修饰超氧化物歧化酶衍生物的制备及其放射性碘标记

Preparation of Superoxide Dismutase Derivative with Polyethylene Glycol Mono Methyl Ether and Its Labeling with Radioactive I^(125)

目的制备聚乙二醇(PEG)修饰超氧化物歧化酶(SOD)衍生物并对其进行放射性碘标记。方法将PEG中加入干苯、PEG单甲醚、氰尿酰氯及无水碳酸钾进行活化,并将活化产物逐渐加入到溶解有SOD的pH9.2四硼酸钠溶液中,制备得PEG-SOD衍生物,经葡聚糖凝胶G75纯化后,以氯胺T与碘125化钠进行放射性标记,并计算标记物的比放射性。结果经葡聚糖凝胶G75纯化后PEG-SOD衍生物的蛋白回收率达到74.1%,碘标记的PEG-SOD比放射性平均值为1.47mCi/mg。结论本文建立的PEG-SOD衍生物制备工艺可行,标记的PEG-SOD符合药理学实验要求,可用于药理学的实验研究。

OBJECTIVE： To prepare the SOD derivative with PEG and its labeling with I^125. METHODS： PEG was activated by cyanuric chloride, polyethylene mono methyl ether and anhydr- carbonicum kalium in absolute benzene. The activated PEG was added to sodium tetraborate solution with pH9.2 with SOD, thus to get derivative of PEG- SOD, which, being purified by dextran gel G75, was labeled with I^125 and chloramines- T oxidation, and the specific radioactivity of the marker was counted. RESULTS： After purified by dextran gel G75, the protein recovery of derivative of PEG - SOD was as high as 74.1%, and the purified PEG-SOD labeled with I^125 had a average radioactivity of 1.47mCi/mg. CONCLUSION： The technology put forward in this paper is practical for preparing PEG - SOD derivative. And the labeled PEG - SOD can meet the requirement of pharmacological experiment, and can be adopted into relevant researches.