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

Abstract

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