Inorganic oxides with potential application in the preparation of a ⁶⁸Ge/⁶⁸Ga generator system

The ion exchange properties of some tin and titanium oxides with potential application in the development of a ⁶⁸Ge/⁶⁸Ga generator were determined. The best potential candidates, SnO₂ and calcined SnO₂, were further characterized by powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) surface area analysis and its radiation stability was also determined. Two ⁶⁸Ge/⁶⁸Ga pilot generators (1.85MBq) based on SnO₂ and calcined SnO₂ were developed and evaluated over 100 and 200 elution cycles respectively, using as eluent different concentrations of HCl. The generator based on calcined SnO₂ showed higher ⁶⁸Ga elution yield and lower ⁶⁸Ge content in the eluate (75-80% and <3×10^-3% respectively, 1-2M HCl) than the generator based on unheated SnO₂ (60-65% and <1×10^-1% respectively, 1-2M HCl). Nano-crystalline calcined SnO₂ proved to be a promising sorbent; therefore it should be considered as an attractive candidate to develop ⁶⁸Ge/⁶⁸Ga generators to produce gallium-68 for biomedical purposes.