~(99)Tc~m-MAG_3-Lys-mPEG的制备及其在小鼠体内的分布

Preparation and Biodistribution of ~(99)Tc~m-MAG_3-Lys-mPEG

摘要: 以mPEG-5000、Fmoc-Lysine和MAG3为原料,经过五步反应合成了载体MAG3-Lys-mPEG;对其进行99Tcm标记后,进一步研究了标记物的体外稳定性及其在小鼠体内的生物分布。结果表明,99Tcm-MAG3-Lys-mPEG的标记率>98%;标记物在体外有很好的稳定性,在生理盐水中放置24 h时,放化纯度>91%;在血清中温浴16.5 h时放化纯度仍>92%;标记物在小鼠体内的血液清除较快,在肾脏中的摄取最高,标记物主要经肾脏通过尿液排出体外。mPEG有可能用作反义核酸的有效载体。

Abstract: Starting with mPEG-5000,Fmoc-Lysine,and mercaptoacetyltriglycine(MAG_3),the carrier MAG_3-Lys-mPEG is synthesized through five steps,which carrier is labeled by ~(99)Tc~m with labeling efficiency >98%.~(99)Tc~m-MAG_3-Lys-mPEG shows high stability in vitro.The radiochemical purity keeps up >91% and >92% after incubation in saline for 24 h and in bovine serum for 16.5 h,respectively.The biodistribution in mice indicates that ~(99)Tc~m-MAG_3-Lys-mPEG is quickly cleared from blood,and excreted mainly through the urinary systemr.There is the highest uptake in kidneys.It is expected that mPEG may be used as an effective ASODN carrier.