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The production of medical radioisotopes for theranostics is essential for the development of personalized nuclear medicine. Among them, radiometals can be used to label proteins and peptides and their supply in quantity and quality suitable for clinical applications represents a scientific challenge. A research program is ongoing at the Bern medical cyclotron, where an IBA Cyclone 18/18 HC is in operation. The cyclotron provides 18 MeV proton beams up to 150 μA and is equipped with a Solid Target Station (STS) and a 6 m Beam Transport Line (BTL), ending in a separate bunker with independent access. A novel magnetic target coin was realized to bombard isotope-enriched materials in the form of compressed powders, together with a compact focalization system to enhance the irradiation procedure. For an optimized production yield with the required radionuclidic purity, novel methods were developed to precisely measure the extracted beam energy and the involved reaction cross sections. In particular, a target station was realized to measure nuclear cross sections using materials in the form of powder deposited on an aluminium disc by sedimentation, bombarded by a monitored flat beam.

RadioNuclide Therapy (RNT) in nuclear medicine is a cancer treatment based on the administration of radioactive substances that specifically target cancer cells in the patient. These radiopharmaceuticals consist of tumor-targeting vectors labeled with β - , α, or Auger electron-emitting radionuclides. In this framework, 67 Cu is receiving increasing interest as it provides β - -particles accompanied by low-energy γ radiation. The latter allows to perform Single Photon Emission Tomography (SPECT) imaging for detecting the radiotracer distribution for an optimized treatment plan and follow-up. Furthermore, 67 Cu could be used as therapeutic partner of the β + -emitters 61 Cu and 64 Cu, both currently under study for Positron Emission Tomography (PET) imaging, paving the way to the concept of theranostics. The major barrier to a wider use of 67 Cu-based radiopharmaceutical is its lack of availability in quantities and qualities suitable for clinical applications. A possible but challenging solution is the proton irradiation of enriched 70 Zn targets, using medical cyclotrons equipped with a solid target station. This route was investigated at the Bern medical cyclotron, where an 18 MeV cyclotron is in operation together with a solid target station and a 6-m-long beam transfer line. The cross section of the involved nuclear reactions were accurately measured to optimize the production yield and the radionuclidic purity. Several production tests were performed to confirm the obtained results., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Saverio Braccini reports financial support was provided by Swiss National Science Foundation., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)