Development of ۱۶۶Ho-zoledronate as a bone marrow ablative agent

In this study, production, quality control and biodistribution studies of ۱۶۶Ho-zoledronate have been presented as a possible bone marrow ablative agent. Ho-۱۶۶ chloride was produced by thermal neutron irradiation of natural ۱۶۵Ho(NO۳)۳ samples. ۱۶۶Ho-zoledronate complex was prepared by adding the desired amount of zoledronate solution (۰.۲ mL, ۱۵۰ mg/ml in ۱ M NaOH) to appropriate amount of the ۱۶۶HoCl۳ solution.  Radiochemical purity of the complex was monitored by instant thin layer chromatography (ITLC). Stability studies of the complex in the final preparation and in the presence of human serum were performed up to ۴۸ h. The biodistribution of ۱۶۶Ho-zoledronate and ۱۶۶HoCl۳ in wild-type mice was checked up to ۷۲ h. ۱۶۶Ho-zoledronate complex was prepared in high radiochemical purity (> ۹۹%, ITLC) and specific activity of ۴.۴ GBq/mmol. The major accumulation of radiolabelled complex was observed in the bone tissue. These findings suggest ۱۶۶Ho-zoledronatehas can be a possible candidate for bone marrow ablation in patients with multiple myeloma.

Keywords:

Bone marrow ablation , Ho-۱۶۶ , Zoledronate , biodistribution