99Tcm-MAG3-RRL肿瘤靶向肽的标记和性质鉴定  

Labeling and Characterization of 99Tc m-MAG3-RRL Tumor Targeting Peptide

作　　者：杜毓菁 闫平[1] 陈钊 姜巧[1] 段小江 王荣福[1,2] DU Yu-jing;YAN Ping;CHEN Zhao;JIANG Qiao;DUAN Xiao-jiang;WANG Rong-fu(Department of Nuclear Medicine,Peking University First Hospital,Beijing 100034,China;Department of Nuclear Medicine,Peking University International Hospital,Beijing 102206,Chin)

机构地区：[1]北京大学第一医院核医学科,北京100034 [2]北京大学国际医院核医学科,北京102206

出　　处：《核化学与放射化学》2020年第3期155-160,I0003,共7页Journal of Nuclear and Radiochemistry

基　　金：国家重大科学仪器设备开发专项(2011YQ03011409);十二五国家支撑项目(2014BAA03B03);北京市科技计划项目(首都健康保障培育研究专项课题,Z181100001618017);北京大学医学青年科技创新平台发展基金(BMU2018MI010)。

摘　　要：将具有肿瘤靶向性的精氨酸-精氨酸-亮氨酸(RRL)多肽与双功能螯合剂MAG3相连,摸索其螯合99 Tcm的适宜标记条件并评价探针的体外稳定性。标记利用SnCl2还原法进行99 Tcm标记,对影响标记的主要变量因素分别进行探究以获得适宜标记条件,采用纸层析法测定标记率和放射化学纯度。实验所得MAG3-RRL纯度为98.94%,适宜标记条件下,标记率为93.67%±1.10%,纯化后放射化学纯度为94.32%±0.19%(n=3)。99 Tcm-MAG3-RRL在生理盐水和50%牛血清白蛋白(BSA)中放置,6h内放射化学纯度均大于90%(n=3),在半胱氨酸溶液中的最高置换率为0.57%±0.21%,生理盐水对照为0.41%±0.04%(n=3,P>0.05)。99 Tc m-MAG3-RRL的脂水分配系数为lg P=-0.15±0.01(n=3)。结果表明:MAG3可成功连接RRL多肽,并能进一步提高标记率;探针制备方法简单快速,体外稳定性好,为进一步的生物学实验提供了良好的基础。Arginine-arginine-leucine(RRL)a tumor targeting peptide is designed to link the bifunctional chelator mercaptoacetyltriglycine(MAG3),aiming to explore the labeling conditions of 99 Tcm and to evaluate the stability of this probe in vitro.Then 99 Tcm was labeled through the SnCl2reduction method,and the main factors affecting the labeling were investigated respectively to obtain the suitable labeling conditions.The paper chromatography was used to determine the labeling rate and radiochemical purity.As a result,the purity of MAG3-RRL is 98.94%.Under the suitable labeling conditions,the labeling rate is 93.67%±1.10%,and the radiochemical purity is 94.32%±0.19%(n=3).When 99 Tcm-MAG3-RRL is placed in normal saline at room temperature and 50%BSA at 37℃,the radiochemical purity of 99 Tcm-MAG3-RRL is more than 90%(n=3)within 6hours.The highest replacement rate of 99 Tcm-MAG3-RRL is 0.57%±0.21%in cysteine solution,and 0.41%±0.04%in normal saline control(n=3,P>0.05).The distribution coefficient lg Pof 99 Tcm-MAG3-RRL is-0.15±0.01(n=3).In conclusion,the results show that MAG3can successfully be connected to RRL polypeptide and further improve the labeling rate,and the preparation method of 99 Tcm-MAG3-RRL is simple and fast.99 Tcm-MAG3-RRL probe has good stability in vitro,which provides a good basis for further biological experiments.

关 键 词：精氨酸-精氨酸-亮氨酸 99 Tcm MAG3 

分 类 号：R817.9[医药卫生—影像医学与核医学]