A Simple Target for the Production of Aqueous [18F] Fluoride Ion Using [18O] Oxygen Gas

60795 Positron emission tomography (PET) is a non-invasive functional imaging technique that measures biochemical/physiological parameters using radiopharmaceuticals labeled with positron-emitting radioisotopes within the human body. The development of a reliable, high yield, and economical method for the cyclotron-produced radioisotope fluorine-18 in the form of [18F] fluoride ion would be beneficial for the growth and increased utilization of PET. This project will develop a practical and reliable method for the use of gaseous [18O] oxygen gas as the target material for aqueous [18F] fluoride ion production. This target offers two important advantages over the current liquid target method: (1) gas targets are able to withstand relatively higher beam currents than liquid targets giving higher yields, and (2) the expensive enriched oxygen-18 gas target material can be more efficiently recovered after the bombardment and received for subsequent runs. In Phase I, a prototype [18O]oxygen gas target was designed, constructed, and tested with a manually-operated target support unit (TSU) and was shown to produce aqueous [18F] fluoride ion in good yield. The TSU allows the cryogenic recovery and recycling of the enriched [18O]oxygen gas. The problem of combining elements of both a high-pressure gas target for the bombardment and a liquid target for the product delivery was solved. Phase II will design and construct a fully functional prototype high-current target and TSU that will be used for automated operations on the current generation of biomedical cyclotrons. Commercial Applications and Other Benefits as described by the awardee: New commercial suppliers and distributors of PET radiopharmaceuticals are being announced regularly as are new medical imaging devices that require these positron-emitter labeled radiotracers. The new target should result in a reliable, high-yield, economical method becoming the new standard method for the production of fluorine-18 radiopharmaceuticals for PET in clinical and research studies