摘要
采用改进的双相氯胺 T法对LL EPO进行碘标记 ,使用离心超滤法分离纯化标记混合物 ,对标记纯化的LL EPO经三氯乙酸沉淀和SDS PAGE法鉴定放化纯度 ,通过网织红细胞法对标记前后的蛋白生物活性进行鉴定。结果表明 :1 改进的双相氯胺 T法标记LL EPO ,其标记率为 89% ,比放射性为 5 82× 1 0 5Bq·μg-1蛋白 ,放化纯度 >96% ,SDS PAGE法鉴定标记产物同原型蛋白电泳行为一致 ,Rf值分别为 0 2 8、0 49,网织红细胞法鉴定的标记蛋白与非标记蛋白的生物活性无差异。2 离心超滤法得到的蛋白回收率为 95 %以上 ,而凝胶过滤法得到的蛋白回收率仅为 2 3 82 % ;
The study is designed to investigate the labelling of LL-EPO, purification of labelled compound, and therefore, to prepare the labelled LL-EPO with high purity and biological activity. LL-EPO was labelled with 125I by the commonused chloramine-T and the modified two-phase chloramine-T method, respectively. The labelled compound was purified by both gel filtration and ultrafiltration method, respectively. The purity of the labelled LL-EPO was determined by both trichloroacetic acid (TCA) and SDS-PAGE method, and the biological activity was determined by the reticulocyte counting method. The results demonstrated that the iodine incorporation and specific radioactivities were 89% and 5.82×10 5Bq·μg -1 for LL-EPO labelled by the modified two-phase chloramine-T method and were 20.65% and 3.62×10 5 Bq·μg -1 for LL-EPO labelled by the common used chloramine-T method, respectively. The purity of labelled LL-EPO purified by both gel filtration and ultrafiltration were over 96% with TCA method purification. The labelled LL-EPO showed two bands with Rf of 0.28 and 0.49, respectively, which is identical to that of standard LL-EPO through SDS-PAGE. There was no loss of biological activity of LL-EPO after labelling as determined by reticulocyte counting method.
出处
《核农学报》
CAS
CSCD
北大核心
2004年第1期55-58,35,共5页
Journal of Nuclear Agricultural Sciences
