Fully automated synthesis of [18F]fluorocholine on GE FASTlab II synthesizer

A reliable and fully automated method for synthesis, purification and formulation of [F-18]FCH on the GE FASTlab II utilizing a single-use cassette was reported. The radiosynthesis sequences of [F-18]FCH was written based on the two-step, gas phase synthesis methodology. Dibromomethane (DBM) was fluorinated with no-carrier-added [F-18]fluoride ion, assisted by K-222/K2CO3, to afford [F-18]fluorobromomethane ([F-18]FBM) as a gas. [F-18]FCH was then prepared by bubbling [F-18]FBM through Sep-Pak Silica cartridges to react with dimethylethanolamine (DMAE) preloaded on Sep-Pak C18 cartridge. The resulting [F-18]FCH was purified using Sep-Pak C18 and Accell CM cartridges in series. The purified [F-18]FCH was eluted from the CM cartridge and formulated with 0.9 % sodium chloride for injection. With this method, the radiochemical yield of [F-18]FCH was 17.8 +/- 2.5 % with a high radiochemical purity (>99 %). Three consecutive [F-18]FCH validation runs were performed, and all quality control parameters met the release criteria for human use. This method is quite straightforward utilizing single-use cassettes. [F-18]FCH was reproducibly produced at sufficiently high radioactive concentration for multiple preclinical or human imaging doses from a single radiosynthesis.