New developments for theranostic radioisotope production with solid targets at the Bern medical cyclotron

The concept of theranostics in nuclear medicine is based on the use of a pair of radioisotopes to label radiopharmaceuticals for both diagnosis and therapy and is essential for nuclear medicine developments. The production of novel medical radioisotopes using solid target stations is challenging and new instruments and methods are needed. A research program is ongoing at the 18 MeV Bern medical cyclotron, equipped with a Solid Target Station and a 6.5 m Beam Transfer Line ending in a separate bunker. To irradiate isotope-enriched materials in form of compressed powder pellets, a novel target coin was conceived and realized together with methods to assess the beam energy and the production cross sections. To optimize the irradiation procedure, a novel ultra-compact active irradiation system based on a specific magnetic lens and a two-dimensional beam detector was conceived, constructed and tested. The system allows to control on-line the size and position of the beam and to correct its characteristics by steering and focusing it in order to keep it on target. The first results on the production of several radionuclides (Sc-43, Sc-44, Sc-47, Cu-61, Cu-64, Cu-67, Ga-68, Er-165, Tm-165, Tm-167 and Tb-155) are presented.