A novel approach to medical radioisotope production using inverse kinematics: A successful production test of the theranostic radionuclide ⁶⁷ Cu

A novel method for the production of important medical radioisotopes has been developed. The approach is based on performing the nuclear reaction in inverse kinematics, namely sending a heavy-ion beam of appropriate energy on a light target (e.g. H, d, He) and collecting the isotope of interest. In this work, as a proof-of-concept, we studied the production of the theranostic radionuclide ⁶⁷ Cu (T _1/2 = 62 h) via the reaction of a ⁷⁰ Zn beam at 15 MeV/nucleon with a hydrogen gas target. The ⁶⁷ Cu radionuclide alongside other coproduced isotopes, was collected after the gas target on an aluminum catcher foil and their radioactivity was measured by off-line γ-ray analysis. After 36 h post irradiation, apart from the product of interest ⁶⁷ Cu, the main radioimpurity coming from the ⁷⁰ Zn + p reaction was ^69m Zn (T _1/2 = 13.8 h), which can be reduced by further radio-cooling. Moreover, along with the radionuclide of interest produced in inverse kinematics, the production of additional radioisotopes is possible by making use of the forward-focused neutrons from the reaction and allowing them to interact with a secondary target. A preliminary successful test of this concept was realized in the present study. The main requirement to obtain activities appropriate for preclinical studies is the development of high-intensity heavy-ion primary beams.