^(99m)Tc直接法标记抗体的3个常用还原剂的评价

Reduction-mediated technetium-99m labeling of antibodies -evaluation of various reducing agents

比较了^（９９ｍ）Ｔｃ直接法标记抗体的３个常用还原剂：氯化亚锡（ＳｎＣｌ_２）， ２－巯基乙醇（２－ＭＥ）和抗坏血酸（ＡＡ）的^（９９ｍ）Ｔｃ标记率、标记抗体的稳定性及免疫活性。结果显示。 ２－ＭＥ是一个良好的还原剂，当抗体／２－ＭＥ摩尔比为１∶２０００时，抗体的标记率可达到９５％以上，胶体形成量少于５％，^（９９ｍ）Ｔｃ－ＢＡＣ_５肿瘤放射免疫显像，鼻咽癌移植瘤影像清晰。

Three common reducing agents: stannous chloride (SnCl_2), ascorbic acid (AA), 2-mercapoethanol (2-ME) have been compared for their efficacy of labeling antibodies(Abs) with ^(99m)Tc, stability and immunoreactivity of labeled Abs The results showed that 2-ME was an optimum reducing agent, at a molar ratio of 1:2000 for Ab to 2-ME. A ^(99m)Tc labeling efficiency greater than 95% can be obtained, the colloid formation was less than 5%. The radioimmunoimaging of ^(99m)Tc-BAC_5 in nude mice bearing tumor xenografts showed that tumor can be viewed clearly.