Tantalum [18O]water target for the production of [18F]fluoride with high reactivity for the preparation of 2-deoxy-2-[18F]fluoro-D-glucose

Abstract

Purpose: To develop a new tantalum [18O]water target for the routine production of reactive, no-carrier-added [18F]fluoride ion in Curie amounts for the synthesis of radiopharmaceuticals.

Procedures: The tantalum target body was filled with 0.86 mL of 95% enriched [18O]water and irradiated with 10.2 MeV protons on target with beam currents of 26-40 microA for 60-90 min. [18F]Fluoride ion produced is trapped in an anion exchange resin cartridge and the expensive [18O]water is recovered for recycling. The [18F]fluoride ion is released from the resin by elution with a dilute solution of K(2)CO(3) and utilized in the synthesis of 2-deoxy-2-[18F]fluoro-D-glucose (FDG).

Results: Using the tantalum target, Curie levels of no-carrier-added [18F]fluoride ion (specific activity: >30,000 Ci/mmol) were reliably and reproducibly produced (n > 100), from which FDG was synthesized in 70% radiochemical yield.

Conclusion: Tantalum [18O]water target body for the production of [18F]fluoride ion has the best characteristics from the standpoint of [18F]fluoride ion recovery and its radiochemical reactivity and low induced activation. This new target has the potential to replace the currently used silver and titanium [18O]targets for the routine production of [18F]fluoride ion.