99Tcm（CO）3-BPHRGD 的制备及其在荷 M21人黑色素瘤裸鼠体内的生物分布

摘要

制备了99 Tcm （CO ）3‐BPHRGD ，并进行了荷 M21人黑色素瘤裸鼠体内生物学评价。在 pH ＝7、75℃条件下反应30 min ，99 Tcm （CO）3‐BPHRGD的标记率大于80％，纯化后标记物的放化纯度大于98％。体外稳定性实验结果显示，37℃下，标记物在生理盐水、人血清中具有很好的稳定性。荷M 21人黑色素瘤裸鼠体内分布显示，注射99 Tcm （CO）3‐BPHRGD后0.5、1、2、4 h ，标记物的瘤／血比分别为0.70±0.45、0.87±0.05、1.10±0.19、1.68±0.04。随着时间的延长，靶与非靶的放射性摄取比（T／N T ）增大，表明该标记物在肿瘤细胞中的清除速度慢于其他组织。通过进一步结构修饰，改变其体内代谢途径及药代动力学性质，99 Tcm （CO）3‐BPHRGD非常有希望成为一种新型肿瘤显像剂。%The 99 Tcm (CO)3‐BPHRGD was prepared ,and in‐vivo biological evaluations in nude mice bearing M 21 human melanoma tumor were completed .The labeling yield of 99 Tcm (CO)3‐BPHRGD is more than 80% under optimal conditions (pH=7 ,reacting at 75 ℃ for 30 min) ,and the radiochemical purity is more than 98% after purification . T he in‐vitro stability experiments show that the radiolabeled compound has good stability in normal saline and human serum under 37 ℃ .The biodistribution of 99 Tcm (CO)3‐BPHRGD in nude mice bearing M21 human melanoma tumor shows that the ratio of tumor/blood is 0.70 ± 0.45 ,0.87 ± 0.05 ,1.10 ± 0.19 and 1.68 ± 0.04 at 0.5 ,1 ,2 and 4 h respectively .The ratio of T/NT increases with time .This indicates that the clear‐ance rate of this radiolebeled compound in tumor is slower than in other tissues . Through the further structural modification to change metabolic pathways and pharma‐cokinetic properties ,it is very promising as a new tumor imaging agent .