Production, Quality Control and Biological Evaluation of ۱۶۶Ho-PDTMP as a Possible Bone Palliation Agent

Objective(s):In this study, ۱۶۶Ho-۱,۲-propylene di-amino tetra(methy۱enephosphonicAcid) (۱۶۶Ho-PDTMP) complex  was prepared as a bone palliation agent. Materials and Methods:The complex was successfully prepared using an in-house synthesized EDTMP ligand and ۱۶۶HoCl۳. Ho-۱۶۶ chloride was obtained by thermal neutron irradiation (۱ × ۱۰۱۳ n.cm-۲.s-۱) of natural Ho(NO۳)۳ samples  followed by radiolabeling and stability studies. Biodistribution in wild type rats was also peformed. Results: The complex was prepared with thespecific activity of ۲۷۸ GBq/mg and high radiochemical purity (>۹۹%, checked by ITLC). ۱۶۶Ho-PDTMP complex was stabilized in the final preparation and in the presence of human serum (>۹۰%) up to ۷۲ hr. The biodistribution of ۱۶۶Ho-PDTMP in wild-type rats demonstrated significant bone uptake was up to ۴۸ hr compared to ۱۶۶HoCl۳. Conclusion: The produced ۱۶۶Ho-PDTMP properties suggest a possible new bone palliative therapeutic to overcome the metastatic bone pains.