Speaker
Description
In recent years, as underlined by the IAEA CRP (Coordinated Research Project) on $^{67}$Cu, $^{47}$Sc, and $^{186}$Re (1), the scientific interest focused on $^{47}$Sc due to its theranostic characteristics making it exploitable both for therapeutic and diagnostic purposes. In fact, in its radioactive decay to the stable $^{47}$Ti, $^{47}$Sc (t$_{1/2}$=3.3492 d) emits γ-rays of the proper energy (E=159.381 keV, I=68.3%) to be used with SPECT (Single Photon Emission Computed Tomography) cameras, together with low-energy β$^{-}$-particles (E$_{mean}$=162.0 keV, I=100%) suitable for the treatment of small-medium sized tumors.
At INFN-LNL, in the framework of LARAMED (LAboratory of RAdionuclides for MEDicine) (2), the possible production routes of $^{47}$Sc using proton beams are investigated in two different projects: PASTA (Production with Accelerator of Sc-47 for Theranostic Applications) and REMIX (Research on Emerging Medical radIonuclides from the X-sections). In PASTA, funded by INFN for the years 2017/2018, the production using $^{nat}$V and enriched $^{48}$Ti targets is studied (3,4). On the other hand, within the REMIX project, funded by INFN for the years 2021/2023, the employment of enriched $^{49}$Ti and $^{50}$Ti is analyzed. Those targets are irradiated in collaboration with the ARRONAX facility (5) where a 70 MeV proton beam is provided by a cyclotron similar to not yet operative one installed at LNL. However, the enriched targets are realized at Legnaro laboratories (6).
In this work, the $^{47}$Sc cross-section values obtained from the proton bombardment of $^{nat}$V targets are presented and compared to the preliminary results achieved when using, instead, enriched $^{49}$Ti targets. Together with $^{47}$Sc, also the cross-sections of the co-produced contaminants are taken into account since they can contribute to the dose delivered to a patient. In particular, $^{46}$Sc (t$_{1/2}$=83.79 d) represents the main contaminant since it is not possible to wait for its decay and it cannot be separated chemically. The results are also compared to the literature data, when available.
(1) A.Jalilian, et al., Curr Radiopharm. 14(4):306-314 (2021).
(2) J. Esposito, et al., Molecules 24(1), 20 (2019).
(3) G. Pupillo, et al., J. Radioanal. Nucl. Chem 322, 1711-1718 (2019).
(4) F. Barbaro, et al., Phys Rev C 104, 044619 (2021).
(5) F. Haddad, et al., Eur. J. Nucl. Med. Mol. Imaging 35(7):1377-1387 (2008).
(6) H. Skliarova, et al., Nucl. Instrum. Methods Phys. Res A 981, 164371 (2020).
