^(99)Tc^(m)直接法标记单克隆抗体的研究Ⅱ.抗坏血酸在直接法标记过程中的作用

STUDY OF A DIRECT METHOD FOR^(99)Tc^(m)LABELING OF MONOCLONAL ANTIBODYⅡ.THE EFFECT OF ASCORBIC ACID IN THE DIRECT LABELING

分析和比较了在^（９９）Ｔｃ~ｍ直接法标记单克隆抗体过程中，抗坏血酸在各个环节中的作用和影响。结果表明，在抗体还原完成后加入防氧化剂抗坏血酸可以防止还原后的—ＳＨ重新氧化，得到的标记产物在标记率和体外稳定性方面均优于不加抗坏血酸的标记法。该方法已成功地用于对Ｆ（ａｂ＇）＿２片段的标记并进行了荷瘤裸鼠体内分布和肿瘤显像测定，得到了很好的体外显像结果。

The effectes of ascorbic acid(AA) on the process of direct labeling of monoclonal antibody are investigated. Based on the comparison of the relevant experimental conditions, it is found that AA has a strong antixidizing effect on reduced antibody and also a stabilizing effect on the labels.Monoclonal antibody fragments F(ab') 2 are successfully labeled using our method. Biodistribu tions of the labels are measured in tumor bearing nude mice. Tumor localization in vitro is also achieved.