中文摘要：

探索用^99Tc^m直接标记表皮生长因子（EGF）的方法并研究其在荷C6动物体内的生物学分布特点。巯基乙醇（20 mL/L）10μL还原EGF（2.5μg）;含0.5μg SnCl2的亚甲基二膦酸盐（MDP）溶液将还原高价锝使之与还原EGF的巯基结合,放化纯度大于95%,标记物稳定性较好,在6 h内放化纯度大于95%。通过内皮细胞培养进行^99Tc^m-EGF的生物活性鉴定,显示EGF在锝标记前后生物学活性未见明显改变（P〉0.05）.^99Tc^m-EGF在荷瘤鼠体内生物学分布显示肝、脾、肾等组织放射性分布较高,瘤区放射性较高,而脑组织最低,4 h瘤与正常组织放射性摄取比值（Tumor/Normal Tissue）为2.25,SPECT全身显像显示瘤组织放射性核素浓聚。因此直接合成的^99Tc^m-EGF可望成为特异性诊断高表达EGFR肿瘤的SPECT分子显像剂。

英文摘要：

The method of technetium-99m direct radiolabeling of epidermal growth factor （EGF） and the biological distribution characteristics of ^99 Tc^m-EGF in C6-bearing rats were ex- plored. Following reduction of EGF（2.5 μg） with 2-ME（20 mL/L, 10 μL）, EGF was labeled with ^99Tc^m in the presence of SnC12 （0.5 μg）. The results show that radiochemical purity of ^99Tc^m-EGF is more than 95% and ^99Tc^mEGF is of the characteristic of stability. The biological activity analyzed by the culture of endothelial cells shows that there is no significant difference between ^99Tc^m-EGF and EGF（P〉0.05）. Biological distribution is observed at different time point after injection of ^99Tc^m-EGF into tumor-bearing Wistar rats, and shows ^99Tc^m-EGF is mainly accumulated in liver, kidney and spleen and least accumulated in the brain. Tumor take relatively high concentration of ^99Tc^m-EGF and the uptake ratio of tumor to normal tissue is 2.25 at 4 h. So ^99 Tc^m-EGF prepared by this direct method appears to be a feasible way to detect the tumors expressing high EGFR（such as glioma）.