Automated production at the curie level of no-carrier-added 6-[18F]fluoro-L-dopa and 2-[18F]fluoro-L-tyrosine on a FASTlab synthesizer

An efficient, fully automated, enantioselective multi-step synthesis of no-carrier-added (nca) 6-[18F]fluoro-L-dopa ([18F]FDOPA) and 2-[18F]fluoro-L-tyrosine ([18F]FTYR) on a GE FASTlab synthesizer in conjunction with an additional high-performance liquid chromatography (HPLC) purification has been developed. A PTC (phase-transfer catalyst) strategy wasused to synthesize these two important radiopharmaceuticals. According to recent chemistry improvements, automationof the whole process was implemented in a commercially available GE FASTlab module, with slight hardware modificationusing single use cassettes and stand-alone HPLC. [18F]FDOPA and [18F]FTYR were produced in 36.3 ± 3.0 % (n = 8) and50.5 ± 2.7 % (n = 10) FASTlab radiochemical yield (decay corrected). The automated radiosynthesis on the FASTlab modulerequires about 52 min. Total synthesis time including HPLC purification and formulation was about 62 min. Enantiomericexcesses for these two aromatic amino acids were always >95 %, and the specific activity of was >740 GBq/μmol. Thisautomated synthesis provides high amount of [18F]FDOPA and [18F]FTYR (>37 GBq end of synthesis (EOS)). The process, fullyadaptable for reliable production across multiple PET sites, could be readily implemented into a clinical good manufacturingprocess (GMP) environment.