Optimization of Ga production at an 18 MeV medical cyclotron with solid targets by means of cross-section measurement of Ga, Ga and Ga.

The future development of personalized nuclear medicine relies on the availability of novel medical radionuclides. In particular, radiometals are attracting considerable interest since they can be used to label both proteins and peptides. Among them, the β-emitter Ga is widely used in nuclear medicine for positron emission tomography (PET). It is used in theranostics as the diagnostic partner of the therapeutic β-emitters Lu and Y for the treatment of a wide range of diseases, including prostate cancer. Currently, Ga is usually obtained via Ge/Ga generators. However, their availability, high price and limited produced radioactivity per elution are a major barrier for a wider use of the Ga-based diagnostic radiotracers. A promising solution is the production of Ga by means of proton irradiation of enriched Zn liquid or solid targets. Along this line, a research program is ongoing at the Bern medical cyclotron, equipped with a solid target station. In this paper, we report on the measurements of Ga, Ga and Ga production cross-sections using natural Zn and enriched Zn material, which served as the basis to perform optimized Ga production tests with enriched Zn solid targets.