Recoiled and Sputtered Radioactive Impurities in 11 MeV Proton-based F-18 Production

One of the quality control measures in F-18 radionuclide production concerns the impurities which might be present in the proton-irradiated enriched H218O target. In this investigation, proton irradiations of enriched water targets were theoretically simulated by the Stopping and Range of Ions in Matter (SRIM) 2013 codes, followed by experimental measurements. First, the SRIM-calculated data were employed to understand the origins of the recoiled and sputtered species. Using a portable Gamma Ray Spectroscopy System, recoiled and sputtered radioactive impurities were measured in the enriched water target following F-18 production using 11 MeV proton beams. The experimental results indicate that Havar window-originated Co-56 radionuclide and silver body-originated Ag-110m radioisotope were identified in the post-irradiated enriched H218O target. In addition, after passing the 18F solution through a column containing Quaternary Methyl Acetate (QMA) resin, none of the radionuclidic impurities were any longer observed to any great extent in the sample.