Quality controls of no-carrier-added aromatic amino acids such as FDOPA and FTYR produced at curie level

Aromatic fluoro amino acids such as 2-[18F]fluoro-L-tyrosine (FTYR) and 6-[18F]fluoro-L-DOPA (FDOPA) are useful radiopharmaceuticals for oncologic studies and evaluation of the presynaptic dopaminergic function using positron emission tomography. Recently, a no-carrier-added (nca) enantioselective synthesis of these compounds, based on an multistep PTC approach was automated in a FASTlabTM module from GE . From 185 GBq of [18F]fluoride and after 1 hour of synthesis, more than 37 GBq of FTYR or FDOPA are available . This automated production yields enough doses for many PET studies. A monograph for FDOPA prepared by electrophilic substitution exists , but it is not adapted to the nca nucleophilic synthesis of FDOPA and FTYR, as in this case specific activity, by products and possible impurities are different. A complete quality control (QC) has then be developed in accordance with the guidelines of the European Pharmacopeia (Eur. Ph.).