Production of [18F] fluoride with a high-current two layer spherical gold target

Background: Fluoride-18 is the most widely used radioisotope for Positron Emission Tomography (PET). [18F] 2-flouro- 2-deoxy D-glucose (FDG) has become a standard tool in the area of clinical research. The oxygen-18 enriched water is the most widely used target for the production of fluoride-18. The use of the nuclear reaction 18O (p,n)18F has been found as the most effective method for the production of [18F] fluoride. Materials and methods: Gold is a chemically resistant metal, which has been found wide application in the chemical industry where it is often used in corrosive environments at high temperature.It is also one of the highest thermal conductivity of metals. A two layer-spherical gold chamber design was chosen to obtain a maximum pressure stability under high beam currents. The target body is consisted of two chambers, internal chamber for internal cooling and external chamber for enriched water target. Results: The target is irradiated with 28 MeV protons energy. The incident energy on the target chamber is 18 MeV. This target is operated without external over-pressure and has been tested for beam currents up to 60 μA. The measured target yield is 2655 MBq/μAh. There is found that saturation yield is 8.3 GBq/μA and shows 80% of theoretical yield. Conclusion: It was observed that gold is a good material for the construction of the target chamber, and also the spherical chambers are the best construction to bearing high pressure under high-current beam condition up to 60 μA. Iran . J. Radiat. Res. 2003 1(2): 119 – 124.