Preparation and evaluation of 188Re(V)-DMSA kit

Objective: To study the preparation of 188Re (V)-dimercaptosuccinic acid (DMSA) and to evaluate the quality of 188Re (V)-DMSA kit. Methods: The complex was prepared by reducing 188Re in the presence of DMSA with stannous chloride in acid medium at pH=1.5. Excess stannous chloride was required and the presence of hydrochloric acid didn' t reduce the yield from 100%. A large dose of ascorbic acid was used to minimize auto-radiolysis. The labeled rate and stability of the kit and the labeled compound stability in vitro were analyzed by high-performance liquid chromatograms (HPLC). Finally the biodistribution of 188Re (V)-DMSA and 99Tcm (V)-DMSA in mice was compared. Results: The labeled rate was 100% and yield was steady in vitro after the compound was kept in room temperature as long as 24 h (>97%). Keeping the kit at -20 degree C and 4 degree C for 3 months the labeled rate was still >95%. Compared with 99Tcm (V)-DMSA, the biodistribution of 188Re (V)-DMSA was similar. Both of them accumulated highest in bone and excreted from kidney. Conclusion: The quality of 188Re(V)-DMSA kit is satisfactory. (authors)