Semi-automatic Synthesis and PET Imaging Evaluation of ¹⁸F-fluoromethylcholine With the Aseptic Inflammation Model

Semi-automated synthesis of ¹⁸F-fluoromethylcholine (¹⁸F-FCH) was achieved with the modification of the commercial synthesis model and the PET imaging of aseptic inflammation model was performed with ¹⁸F-FCH. ¹⁸FCH₂Br as a ¹⁸Ffluoromethylation agent was prepared by the fluorination of dibromomethane followed by distillation from the reaction vessel. The obtained ¹⁸FCH₂Br then reacted with N, N-dimethylamino ethanol loaded on the Sep Pak tC18 cartridge to give ¹⁸F-FCH. After being purified on the solid-phase extraction cartridges, ¹⁸F-FCH was obtained with 12%±2% radiochemical yields (n=3, decay not corrected), and higher than 95% radiochemical purity. The synthesis time was less than 35 min. PET imaging showed that ¹⁸F-FCH had a slightly lower uptake than ¹⁸F-FDG in the inflammation tissues infected with turpentine oil, suggesting a potential use of ¹⁸F-FCH to differentiate between a tumor and inflammation by PET imaging.