氮杂苯并15-冠-5和联吡啶^(99m)Tc标记物的制备及其生物分布

PREPARATION AND BIODISTRIBUTION OF NOVEL ^(99m)Tc COMPLEX WITH AZABENZO15-CROWN-5 AND 2,2'-BIPY

利用协同配位原理研究了在生理盐水中以氮杂苯并 15 冠 5 (L)和 2 ,2′ 联吡啶 (Bipy)为配体的新的99mTc标记物 .在Na2 CO3 和NaHCO3 缓冲体系中 ,以NaBH4为还原剂 ,L和Bipy均取 5mg,在pH =9.4 7～ 10 .0 8范围内 ,标记率达到 80 % ;当pH =9.90 ,反应时间为 5 0min时 ,标记率达到最大值 90 % .在相同实验条件下 ,2种配体均不能单独标记99mTc .标记物在小鼠体内的生物分布实验结果表明 ,标记物有一定的骨摄取 ,其可能的组成为 [99mTc·L·Bipy·n(H2 O) ]3 + .标记物的主要清除途径可能为尿代谢 ,代谢过程中可能生成了某种脂溶性较好的代谢产物 .标记物的血液清除速率有待改进 。

A novel 99m Tc complex with azabenzo15 crown 5 (L) and 2,2′ bipyridine (Bipy), a new candidate for radiopharmaceutical, is prepared and its biodistribution in mice is investigated in saline. The labeled ratio of 99m Tc, with a maximum 90% under pH=9.90 and the reaction time 50min, is 80% using 5mg L, 5mg Bipy and reductant NaBH 4 in Na 2CO 3 and NaHCO 3 buffer solution within pH 9.47～10.08, while either ligand failed to label 99m Tc separately under the same condition. The biodistribution results reveal some bone uptake indicating a possible composition of [ 99m Tc[DK]·L·Bipy· n (H 2O)] 3+ and a urinary metabolism way producing some more hydrophobic metabolite. The improvement of elimination in blood for the complex is needed to obtain higher activity ratio of tissue to blood. 3+ and a urinary metabolism way producing some more hydrophobic metabolite. The improvement of elimination in blood for the complex is needed to obtain higher activity ratio of tissue to blood.