Cross section measurement of terbium radioisotopes for an optimized 155Tb production with an 18 MeV medical PET cyclotron

Gaia Dellepiane; Pierluigi Casolaro; Chiara Favaretto; Pascal V Grundler; Isidre Mateu; Paola Scampoli; Zeynep Talip; Nicholas P van der Meulen; Saverio Braccini

doi:10.1016/j.apradiso.2022.110175

Cross section measurement of terbium radioisotopes for an optimized ¹⁵⁵Tb production with an 18 MeV medical PET cyclotron

Appl Radiat Isot. 2022 Jun:184:110175. doi: 10.1016/j.apradiso.2022.110175. Epub 2022 Mar 9.

Authors

Gaia Dellepiane¹, Pierluigi Casolaro², Chiara Favaretto³, Pascal V Grundler⁴, Isidre Mateu², Paola Scampoli⁵, Zeynep Talip⁴, Nicholas P van der Meulen⁶, Saverio Braccini²

Affiliations

¹ Albert Einstein Center for Fundamental Physics (AEC), Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland. Electronic address: gaia.dellepiane@lhep.unibe.ch.
² Albert Einstein Center for Fundamental Physics (AEC), Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.
³ Center for Radiopharmaceutical Sciences, ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland; Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland.
⁴ Center for Radiopharmaceutical Sciences, ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.
⁵ Albert Einstein Center for Fundamental Physics (AEC), Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland; Department of Physics "Ettore Pancini", University of Napoli Federico II, Complesso Universitario di Monte S. Angelo, 80126 Napoli, Italy.
⁶ Center for Radiopharmaceutical Sciences, ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland; Laboratory of Radiochemistry, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.

PMID: 35344829
DOI: 10.1016/j.apradiso.2022.110175

Abstract

¹⁵⁵Tb [t_1/2 = 5.32 d, E_γ = 87 keV (32%); 105 keV (25%) (IAEA, 2021)] is a novel promising radionuclide for theranostic applications in nuclear medicine. Its physical properties make it suitable for single photon emission computed tomography (SPECT) imaging, while its chemistry allows it to be used as a diagnostic partner for therapeutic radiolanthanides or pseudo-radiolanthanides, such as ¹⁷⁷Lu and ⁹⁰Y. Moreover, ¹⁵⁵Tb could be used as a precise diagnostic match for the β^--emitter ¹⁶¹Tb, opening doors for the true theranostics concept. The availability of ¹⁵⁵Tb in quantity and quality suitable for medical applications is an open issue and its production with medical cyclotrons via the ¹⁵⁵Gd(p,n)¹⁵⁵Tb and ¹⁵⁶Gd(p,2n)¹⁵⁵Tb nuclear reactions represents a possible but challenging solution. For this purpose, an accurate knowledge of the production cross sections is mandatory. In this paper, we report on the measurement of the production cross sections of ¹⁵⁵Tb and other terbium radionuclides formed by proton irradiation of ^natGd₂O₃, ¹⁵⁵Gd₂O₃ and ¹⁵⁶Gd₂O₃ enriched targets, performed at the Bern University Hospital cyclotron laboratory. On the basis of the obtained results, the production yield and purity were calculated to assess the optimal irradiation conditions. The results of several production tests are also presented.

Keywords: Cross sections; Medical cyclotron; Proton irradiation; Radionuclide production; SPECT/CT imaging; Solid target; Terbium-155; Theranostics.

MeSH terms

Cyclotrons*
Humans
Positron-Emission Tomography / methods
Radioisotopes / chemistry
Terbium* / chemistry
Tomography, Emission-Computed, Single-Photon / methods

Substances

Radioisotopes
Terbium