64Cu and 67Cu radionuclide to diagnose and treat of cancer: Experimental and theoretical Production yields
As the number of patients suffering from different cancers has been increased, researchers have evaluated several ways to diagnose and treat these abnormalities. In this regard, application of radionuclides is an interesting option through which some cancers can be simultaneously diagnosed and treated. Radionuclides used in medicine can be produced through nuclear reactors, linear accelerators, generators, fission and fusion.
64Cu is one of the most useful radionuclide as a theranostic agent with γ, β+ and β– decay (E.C. (43.53%), β– (38.48%) and β+ (17.52%); End-point Eβ+ = 653 keV, End-point Eβ– = 579 keV, Eg=1345.84 keV, Iγ = 0.47%) and also 12.7 h half-life making it an interesting option in Positron Emission Tomography (PET) imaging and targeted endoradiotherapy. 64Cu can be produced with 63Cu(n,g)64Cu and 64Zn(n,p)64Cu reactions in nuclear reactor. Another copper radionuclide is 67Cu with γ and β– decay (E mean β– = 141 keV) , Eγ = 184 keV (46.7%), 93 keV (16.60%), 91 keV (7.26%)) and 2.576 days half-life which is useful in radioimmunotherapy, Single Photon Emission Computed Tomography (SPECT) imaging and tracer kinetic studies. It can be produced with 67Zn(n,p)67Cu reaction. The decay schematic of 64Cu and 67Cu is shown in Figure 1.
The present study examined these reactions with natZnO, natZnO nanoparticles (NPs), natCu and natCu-NPs targets in Tehran Research Reactor (TRR) for 64Cu and 67Cu radionuclides productions. Radioactive nanoparticles enjoy the ability of having several radioactive atoms. The prepared samples were inserted in one of the irradiation box of nuclear reactor core with the significant thermal and fast neutron flux about 30 minutes. After cooling times, the irradiated samples were pulled out from the reactor core and prepared for gamma spectrometry with a high purity p-type detector (HPGe). The production yields were also assessed with HPGe detector.
Theoretical calculation of radionuclide production yields required consideration of several different physical parameters such as reaction cross section, radiation time, half-time and neutron flux. Cross section parameters were calculated with benefit nuclear codes such as TALYS-1.8 (the last update). The production yields of 64Cu and 67Cu were calculated using MCNP code which needs to simulate the reactor core of TRR with a maximum power of 5 MW, pool type with 9×6 grid plate containing cool fuel elements, radiation box and etc. This reactor is designed for research, train and production of radionuclides. The theoretical and experimental production yields were compared to each other which showed a good agreement between them. Therefore, MCNPX can be used to optimize radionuclide production condition in the nuclear reactor. On the other hand, comparing the experimental production yields with nano target showed insignificant changes.
Zahra Karimi 1, Mahdi Sadeghi 2, Mostafa Jalilifar 2
1Department of Medical Radiation Engineering, Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan, Iran
2Medical Physics Department, School of Medicine, Iran University of Medical Sciences, P.O. Box: 14155-6183, Tehran, Iran
64Cu, a powerful positron emitter for immunoimaging and theranostic: Production via natZnO and natZnO-NPs.
Karimi Z, Sadeghi M, Mataji-Kojouri N
Appl Radiat Isot. 2018 Jul