Optimization of zirconium-89 production in IBA Cyclone 18/9 cyclotron with COSTIS solid target system

Zirconium-89 is a promising radionuclide in the development of new immuno-PET agents for in vivo imaging of cancerous tumours and radioimmunotherapy (RIT) planning. Besides the convenient half-life of 78.4 h, 89Zr has a beta plus emission rate of 23% and a low maximum energy of 0.9 MeV, delivering good spatial resolution as a result of short positron range in tissue (around 1 mm). Cyclotron production for the radiometal of 89Zr was investigated to find optimal conditions according to results of FLUKA code Monte Carlo modelling of irradiation processes, nuclear reactions and target design. This was followed by reasonably detailed experimental validation (making cyclotron productions for expected high product yield and low impurities levels followed by activity measurements, spectra acquisitions and chemical separation procedures), in which the strategies developed by computer models were carried out in the IBA Cyclone 18/9 cyclotron, permitting a comparison of the predicted and actual yields of 89Zr and isotopic by-products (impurities). Once the in silica model was validated experimentally, then optimal method of the radiometal production in the cyclotron was developed.