Vol.:(0123456789) 1 3 Journal of Radioanalytical and Nuclear Chemistry https://doi.org/10.1007/s10967-019-06903-0 Analysis of radionuclide production in cyclotrons for application in positron emission tomography (PET) José Ródenas 1  · Eva Jabaloyas 1 Received: 22 July 2019 © Akadémiai Kiadó, Budapest, Hungary 2019 Abstract The present work focuses on the analysis of nuclear reactions that can occur in a cyclotron for the generation of radionuclides compliant with the restrictions necessary for medical use in a PET. These radionuclides ought to meet some features, such as being positron emitters and having a half-life as short as possible, considering the times of processing and administration of the radiopharmaceutical. The radionuclides studied, 61 Cu, 64 Cu and 68 Ga, meet these conditions. A commercial cyclotron has been modelled with an energy of 18 MeV for protons. Several simulations have been carried out with the model, using difer- ent materials as a target. The model validation has been done comparing results with experimental data from the literature. Keywords Nuclear reactions · Cyclotron · Monte Carlo · Radiopharmaceuticals · Positron emission tomography · Production of radionuclides Introduction Currently, Positron emission tomography (PET) is one of the most widely used Nuclear Medicine techniques in Radiodi- agnosis for the obtention of in vivo images of the biochemi- cal processes in the human body. It is a non-invasive tech- nique used to evaluate the functioning of organs and tissues through the administration of radiopharmaceuticals. The main drawback of this technique is the difculty to obtain the radionuclides used for labelling the substance injected into the patient to carry out the procedure. Therefore, many medical centres have opted for the use of modular cyclotrons in their facilities to obtain the necessary radionuclides, and that gives them more fexibility to plan the diagnostic processes. Access to commercial cyclotrons has opened diferent research felds, and the main studies focus on radiologi- cal protection in medical centres, oriented towards both patients and workers [1], and studies related to obtaining radionuclides with better characteristics than those tradition- ally considered [2–4]. Isotopes such as 11 C or 15 O have been typically used, since these elements are naturally found in biological mol- ecules and stable nuclides can be easily replaced by radioac- tive isotopes. However, the interest in the use of new radio- isotopes has increased in recent times, especially those of the metal family, such as 68 Ga, 61 Cu or 64 Cu, since they may have better properties concerning half-life, the decay chain or the dose provided to the patient. Consequently, the need to conduct a study on obtaining non-conventional radionuclides for application as radiophar- maceuticals in PET has been identifed [2, 3]. This study is conducted using a model developed in MCNP6 of a cyclo- tron of commercial characteristics to simulate diferent reac- tions. Thus, there will be a tool available to simulate the production of diferent radioisotopes depending on the target used and the operating conditions. Theory Radiopharmaceuticals Radiopharmaceuticals are biological molecules with a radioisotope attached to their structure. These radioactive drugs can be used as diagnostic and therapeutic agents. * José Ródenas jrodenas@iqn.upv.es Eva Jabaloyas evjaca1@gmail.com 1 Department of Chemical and Nuclear Engineering, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain