Speaker
Description
T.M. Bakhshiyan1,2*, G.H. Hovhannisyan2
1Institute of Applied Problems of Physics
of the National Academy of Sciences of the Republic of Armenia,
25 Hrachya Nersisyan, Yerevan, Armenia, 0014
2Yerevan State University, 1 Alex Manoogian Str., Yerevan, Republic of Armenia, 0025
Given the growing prospects for the widespread use of isotopes in nuclear medicine, such as in SPECT/CT and PET/CT diagnostics, functional imaging, targeted therapies, etc., the number of methods for isotope production continues to grow. Since the second half of the 20th century, scientists worldwide have been searching for inexpensive, simple, and reliable methods to produce indium-111 (¹¹¹In) with high radiochemical and chemical purity. Each production method has its own advantages and limitations. In this review, we analyze the available routes for obtaining ¹¹¹In, comparing our experimental results with published data. The aim of this analysis is to study alternative methods for obtaining the 111In isotope and to compare them with common methods, such as proton-induced reactions on cadmium isotopes and alpha-induced reactions on gold isotopes․
In our experiments, we investigated nuclear reactions on enriched tin targets induced by protons and photons, taking advantage of the availability of a compact medical cyclotron and a linear electron accelerator in Yerevan. A stack of enriched (63.2%) ¹¹⁴Sn foils was irradiated using an 18 MeV proton beam provided by the IBA Cyclone18/18 cyclotron. The cross sections for the 114Sn(p,α)¹¹¹In reaction were measured using the stacked-foil activation technique. This method allows for the determination of excitation functions at multiple proton energies simultaneously, under identical irradiation conditions. Additionally, an enriched (92.6%) ¹¹²Sn target was irradiated at the LUE-75 linear electron accelerator of the A. Alikhanian National Science Laboratory at the bremsstrahlung endpoint energy Eγmax = 55 MeV. The cross section per equivalent quantum for reaction 112Sn(γ,x)111In, have been measured via the method of activation and off-line γ-ray spectrometric technique.
Our research allows us to conclude that it is possible to use the photonuclear method for the production of 111In if the proton beam is not available.
