基于双功能螯合剂的99mTc间接标记depreotide的探索

摘要

Objective To explore the use of bifunctional chelating agents for indirect 99mTo-labeling of depreotide. Methods Three kinds of chelating agents HYNIC, NHS-MAG3 and SHNH were applied for indirect labeling of depreotide with 99mTc. Results All three labeling systems had high labeling rate, radiochemistry purity and activity. 99mTc-MAG3-depreotide was more stable in room temperature, serum and plasma. The distribution of 99mTc-HYNIC-depreotide and 99mTc-SHNH-depreotide was significantly higher in blood, heart, stomach and intestine. 99mTc-MAGS-depreotide was mainly excreted from kidney; its clearance in the blood, liver and the kidney was faster, and the radioactive distribution in heart, lung, muscle, bone and brain tissue was lower. Conclusion Indirect 99mTo-labeling of depreotide using bifunctional chelating agents may provide necessary laboratory basis for its future clinical application.%目的 探索使用采用双功能螯合剂作为偶联剂进行间接标记,以避免直接标记所带来的损伤.方法 使用近年来常用的三种螯合剂HYNIC、NHS -MAG3及SHNH进行间接标记.结论 三种标记体系的标记率、放化纯及比活度较高,为核素分子显像提供了必要的基础条件和临床应用前景.稳定性测定发现99mTc-MAG3-depreotide 在室温、血清以及血浆中更稳定.99mTc-HYNIC-depreotide和99mTc-SHNH-depreotide在血液、心脏、胃、肠的分布显著较高.而99mTc-MAG3-depreotide标记物主要经过肾脏排出体外,在血液、肝脏和肾脏中清除较快,而心脏、肺、肌肉、骨骼和脑组织放射性分布均较低,且在整个过程中变化不显著.