Appraisal and simulation of 125I production yield with Low/Medium energy proton and deuteron particles on tellurium targets

The physical production yield (MBq/µA.h and mCi/µA.h) versus proton and deuteron energy (MeV). • 125 Te(p,n) 125 I and 124 Te(d,n) 125 I reactions were simulated by TALYS code to calculate 125 I production yield. • The 126 Te(p,2n) 125 I reaction cross section was also assessed besides competing reactions. • Medium deuteron and proton energies was considered up to 20 and 30 MeV from Karaj cyclotron, respectively. • The production yields were estimated to be 0.805 and 3.84 MBq/µA.h, respectively, at 20 MeV deuterons and 30 MeV protons. The radioisotope iodine-125 has been proposed for use in brachytherapy in nuclear medicine. Currently, 125 I is mainly produced by neutron irradiation of xenon gas in nuclear reactors, although cyclotron-based production can also be investigated. In this research, the cyclotron in Karaj with deuteron energy of 20 MeV and proton energy of 30 MeV was considered to simulate the production of 125 I using 124/125 Te targets. Here, the 125 Te(p,n) 125 I and 124 Te(d,n) 125 I reactions cross sections were analyzed via TALYS code in optical potential model by changing diffusivity and radius, level density model, density of exciton model constituents, pre-equilibrium and equilibrium model by Hauser-Feshbach formalism, branching rates, and possibility of derived particle generation. Additionally, the cross section of 126 Te(p,2n) 125 I reaction was evaluated besides the cross sections of competing reactions. The production yields of the two types of interactions were calculated at different incident particles energies. The maximum cross-section data for 125 I production via (p,n) reaction was estimated to be 684 mb at 11 MeV and for the (d,n) reaction to be 233 mb at 9 MeV. These reactions gave the 125 I production yield of 1.22 and 0.188 MBq/µA.h at these energies, respectively. The calculated cross-sections data for both incident particles energies were plotted and compared with other reports. In curve fitting, the least-square Pade approximation was used with distinct parameters on designated points with χ2 of 0.98 and 0.87 for (d,n) and (p,n) reactions, correspondingly. The maximum uncertainty was estimated to be 6.5 % for 12 MeV deuterons and 12.9 % for 9 MeV protons. The combination of 125 I with other therapeutic radionuclides such as gold and terbium may improve the chances of treatment by increasing the rate of cancer cell killing. Remarkably, the integration of therapy and diagnosis can represent a significant advance in tailored cancer treatment.