@article{renaldin_study_2023,
	title = {Study of thulium-167 cyclotron production: a potential medically-relevant radionuclide},
	volume = {11},
	issn = {2296-2646},
	url = {https://www.frontiersin.org/articles/10.3389/fchem.2023.1288588/full},
	doi = {10.3389/fchem.2023.1288588},
	shorttitle = {Study of thulium-167 cyclotron production},
	abstract = {Introduction:
              Targeted Radionuclide Therapy is used for the treatment of tumors in nuclear medicine, while sparing healthy tissues. Its application to cancer treatment is expanding. In particular, Auger-electron emitters potentially exhibit high efficacy in treating either small metastases or single tumor cells due to their short range in tissue. The aim of this paper is to study the feasibility of a large-scale production of thulium-167, an Auger-electron emitter radionuclide, in view of eventual systematic preclinical studies.
            
            
              Methods:
              Proton-irradiated enriched erbium-167 and erbium-168 oxides were used to measure the production cross sections of thulium-165, thulium-166, thulium-167, and thulium-168 utilizing an 18-{MeV} medical cyclotron equipped with a Beam Transport Line ({BTL}) at the Bern medical cyclotron laboratory. The comparison between the experimental and the {TENDL} 2021 theoretical cross-section results were in good agreement. Additional experiments were performed to assess the production yields of thulium radioisotopes in the {BTL}. Thulium-167 production yield was also measured irradiating five different target materials (
              167
              Er
              2
              O
              3
              ,
              168
              Er
              2
              O
              3
              ,
              
                nat
              
              Tm
              2
              O
              3
              ,
              
                nat
              
              Yb
              2
              O
              3
              ,
              171
              Yb
              2
              O
              3
              ) with proton beams up to 63 {MeV} at the Injector {II} cyclotron of Paul Scherrer Institute.
            
            
              Results and Discussion:
              Our experiments showed that an 8-h irradiation of enriched ytterbium-171 oxide produced about 420 {MBq} of thulium-167 with a radionuclidic purity of 99.95\% after 5 days of cooling time with a proton beam of about 53 {MeV}. Larger activities of thulium-167 can be achieved using enriched erbium-168 oxide with a 23-{MeV} proton beam, obtaining about 1 {GBq} after 8-h irradiation with a radionuclidic purity of
              
                
                  {\textless}
                
              
              99.5\% 5 days post end of bombardment.},
	pages = {1288588},
	journaltitle = {Frontiers in Chemistry},
	shortjournal = {Front. Chem.},
	author = {Renaldin, Edoardo and Dellepiane, Gaia and Braccini, Saverio and Sommerhalder, Alexander and Zhang, Hui and Van Der Meulen, Nicholas P. and Eichler, Robert and Talip, Zeynep},
	urldate = {2023-11-29},
	date = {2023-10-19},
	keywords = {scientific-publication},
}