Fully Automated Macro- and Microfluidic Production of [⁶⁸Ga]Ga-Citrate on mAIO^® and iMiDEV^TM Modules

⁶⁸Ga-radionuclide has gained importance due to its availability via ⁶⁸Ge/⁶⁸Ga generator or cyclotron production, therefore increasing the number of ⁶⁸Ga-based PET radiopharmaceuticals available in clinical practice. [⁶⁸Ga]Ga-citrate PET has been shown to be prominent for detection of inflammation/infection of the musculoskeletal, gastrointestinal, respiratory, and cardiovascular systems. Automation and comparison between conventional and microfluidic production of [⁶⁸Ga]Ga-citrate was performed using miniAllInOne^® (Trasis) and iMiDEV™ (PMB-Alcen) synthetic modules. Fully automated procedures were elaborated for cGMP production of tracer. In order to facilitate the tracer approval as a radiopharmaceutical for clinical use, a new method for radiochemical identity determination by HPLC analysis to complement standard TLC radiochemical purity measurement was developed. The results showed higher radiochemical yields when using MCX cartridge on the conventional module mAIO^®, while a PS-H+ cation exchanger was shown to be preferred for integration into the microfluidic cassette of iMiDEV™ module. In this study, the fully automated radiosynthesis of [⁶⁸Ga]Ga-citrate using different synthesizers demonstrated reliable and reproducible radiochemical yields. In order to demonstrate the applicability of [⁶⁸Ga]Ga-citrate, in vitro and in vivo studies were performed showing similar characteristics of the tracer obtained using macro- and microfluidic ways of production.