⁴⁴Sc production from enriched ⁴⁷TiO₂ targets with a medical cyclotron

⁴⁴Sc is a β⁺-emitter which has been extensively studied for nuclear medicine applications. Its promising decay characteristics [t_1/2 = 3.97 h, E [Formula: see text] = 632 keV (94.3%), E_γ = 1157 keV (99.9%); 1499 keV (0.91%)] make it highly attractive for clinical PET imaging, offering an alternative to the widely used ⁶⁸Ga [t_1/2 = 67.7 min, E [Formula: see text] = 836 keV (87.7%)]. Notably, its nearly fourfold longer half-life opens avenues for applications with biomolecules having extended biological half-lives and enables the centralized distribution of ⁴⁴Sc radiopharmaceuticals. An additional advantage of employing ⁴⁴Sc as a diagnostic radioisotope lies in its counterpart, the β^--emitter ⁴⁷Sc, which is currently under investigation for targeted radiotherapy. Together, they form an ideal theranostic pair, providing a comprehensive solution for both diagnostic imaging and therapeutic applications in nuclear medicine. At the Bern medical cyclotron, a study to optimize the production of scandium radioisotopes is currently ongoing. In this context, proton irradiation of titanium targets has been investigated, exploiting the reactions ⁴⁷Ti(p,α)⁴⁴Sc and ⁵⁰Ti(p,α)⁴⁷Sc. This approach enables the production of Sc radioisotopes within a single PET medical cyclotron facility, employing identical chemical procedures for target preparation and post-irradiation processing. In this paper, we report on cross-section measurements of the ⁴⁷Ti(p,α)⁴⁴Sc nuclear reaction using 95.7% enriched ⁴⁷TiO₂ targets. On the basis of the obtained results, the production yield and purity were calculated to assess the optimal irradiation conditions. Production tests were performed to confirm these findings.