Automated Radiosynthesis of ZD2-[68Ga-NOTA]

The radiosynthesis of ZD2-[⁶⁸Ga-NOTA] was performed in closed-system fully automated Scintomics GRP^® synthesizer (Furstenfeldbruck, Germany) as reported previously.8 (link) Briefly, ⁶⁸Ge/⁶⁸Ga generator (model IGG-100) was used as a source of radionuclide. In the process of automated synthesis, ⁶⁸Ga(III) was eluted from a generator with 0.1 M hydrochloric acid, and the eluent was diluted with water. The resulting solution was passed through the cationic exchange PS-H+ cartridge and subsequently eluted with 5 M sodium chloride solution into a pre-heated reactor containing ZD2-NOTA and HEPES buffer. The labeling was performed in 10 min at 125°C. After reaction, the reaction content was transferred onto C18 Plus Light SPE-cartridge, and the labeled ZD2-(⁶⁸Ga-NOTA) was eluted with a mixture of water for injection/ethanol (1/1, v/v) through the 0.22 µm membrane sterile filter into the final product vial. Finally, the product was diluted with a PBS buffer through the same sterile 0.22 µm membrane filter into the final product vial. Samples are then aseptically removed for quality control testing.