Synthesis, 99mTc(CO)3-labeling and preliminary biodistribution studies of a novel colchicine complex

Abstract

This work reports the synthesis, radiolabeling and preliminary biodistribution results in tumor-bearing mice of [99mTc(CO)3(PA-TZ-CHC)]+. The novel colchicine (CHC) ligand was successfully synthesized via “click” reaction. Radiolabeling was performed in high yield with [99mTc(CO)3]+ core to get [99mTc(CO)3(PA-TZ-CHC)]+, which was hydrophilic and cationic, and was stable at room temperature. Biodistribution studies in tumor-bearing mice showed that [99mTc(CO)3(PA-TZ-CHC)]+ accumulated in the tumor with good uptake while comparatively low retention. The clearance of the 99mTc-complex from normal organs was fast, resulting in increasing tumor/blood and tumor/muscle ratios. The promising results in preliminary biodistribution studies warrant further research to improve tumor targeting efficacy and pharmacokinetic profile of radiolabeled CHC derivative by structural modification.