Method for the preparation of reactive [18] f fluoride

A method to extract out of an aqueous solution, concentrate and/or reformulate [18F] fluorides without any evaporation step, in particular without any azeotropic evaporation step, said extraction, concentration and/or reformulation process comprising the following steps of:

• passing said aqueous [18F] fluoride solution through a solid phase extraction column containing a modified non-ionic solid support (SS) so that that said [18F] fluorides are trapped on the solid support,
• optionally purging the SS with a neutral solvent or flushing the SS with a gas, to remove most of the residual water,
• eluting the [18F] fluorides in an organic solvent or in a mixture of organic solvents suitable for radiolabelling,
• characterised in that said modification of the non-ionic SS has been performed prior to the [18F] fluoride extraction process, by causing the adsorption of a trapping agent (TA) on the SS, said TA being selected for its ability to trap the [18F] fluoride in an anion exchange process so that to form a TA-[18F] species, itself able to remain adsorbed on the SS, the couple SS-TA being selected in such a way that most of the TA is able to remain on the SS during the transit of the aqueous [18F] fluoride solution through the column, while being easily eluted in an organic solvent or in a mixture of organic solvents suitable for radiolabelling.