Fast and reliable generation of [ 18 F]triflyl fluoride, a gaseous [ 18 F]fluoride source.

A novel strategy for the production of reactive [F-18]fluoride has been developed, omitting time consuming azeotropic drying procedures. Gaseous [F-18]triflyl fluoride is formed instantaneously at room temperature from hydrated [F-18]fluoride, followed by distillation in less than 5 minutes into a dry aprotic solvent, in which dry [F-18]fluoride is released in presence of base with >90% radiochemical yield. The reactivity of the [F-18]fluoride has been confirmed by reaction with several model compounds and by the synthesis of the PET tracers [F-18]fluoroestradiol ([F-18]FES) and O-2-[F-18]fluoroethyl-l-tyrosine ([F-18]FET), providing good isolated radiochemical yields and molar activities of up to 123 GBq mol(-1).