Production of radio-isotopes of medical interest: cross sections measurements and comparisons with theoretical models, seminar by C. Duchemin (Subatech)

par Mlle Charlotte DUCHEMIN (Laboratoire SUBATECH UMR 6457)

vendredi 20 mars 2015, 10:30 → 11:30 Europe/Paris

seminar room, 2nd floor (bat 27)

The SUBATECH laboratory and the ARRONAX [1] cyclotron work in close collaboration on the production of radionuclides of medical interest. Some of them are already produced at ARRONAX as Copper-64 for imaging purposes and the Strontium-82 for use in the generator Strontium-82/Rubidium-82 for cardiac imaging. Some others are under developments like Astatine-211 for alpha targeted therapy. Others radionuclides are identified by the scientific community as of interest for medicine. Among them, Thorium-226 [2] (α emitter) has a great potential for leukemia therapies; Rhenium-186 [3] (β- emitter) has shown successful results on bone metastases palliation; Terbium-155 could be used in therapy using Auger electrons and Scandium-44 (gamma/β+ emitter) is the heart of the “three-gamma imaging" concept [4] developed at the SUBATECH laboratory (Nantes). To be able to define production yields and production scenarios, a good knowledge of the production cross section is needed. For these radionuclides, their cross sections are not well-known and/or need further developments, this is why cross section measurements were performed at the ARRONAX cyclotron using the stacked-foil technique and using deuterons as projectiles for the production of the previous cited radionuclides [5, 6, 7]. During this seminar, I will focus on the results obtained on the irradiation of a Thorium-232 target by deuterons to produce Thorium-226. Experiments using protons as projectile have been also performed for comparisons. Indeed, these two light charged particles permit to produce that radionuclide by direct production, but also fissions fragments of medical interest. Among these, Molybdenum-99, worldwide used to fill Mo-99/Tc-99m generator, is produce in large quantities. Its production yield has been determined up to 34 MeV with deuterons and up to 70 MeV with protons. These data allow us to compare both production routes [5] and with other alternative production routes for Mo-99. Using the collected data, comparisons with theoretical models can be made. We have selected the TALYS code [8] and I will expose the results and show some changes made on this code to better reproduce the experimental data. [1] Haddad, F. et al., Arronax a high-energy and high-intensity cyclotron for nuclear medicine. Eur. J. Nucl. Med. Mol. Imaging, 35, 1377-1387 (2008). [2] Friesen, C. et al., Radioimmunotherapy using anti-CD33 antibodies radiolabeled with thorium-226 or bismuth-213 overcome chemo and radioresistance in myeloid leukemia cells, Haematologica ; 94 ; [suppl.2]:329 (2009). [3] Palmedo, H. et al, Painful Multifocal Arthritis: Therapy with Rhenium 186 Hydroxyethylidenedi-phosphonate (186Re HEDP) after Failed Treatment with Medication -Initial Results of a Prospective Study. Radiology;221:256–60 (2001). [4] Grignon, C. et al., “Nuclear medical imaging using beta+ gamma coincidences from Sc-44 radio-nuclide with liquid xenon as detector medium,” Nucl. Instrum. Meth. A 571, 142-145 (2007) [5] Duchemin, C., Guertin, A., Haddad, F., Michel, N. and Métivier, V., Production of medical isotopes from a thorium target irradiated by light charged particles up to 70 MeV, Phys. Med. Biol. 60 (2015) 931-946. [6] Duchemin, C., Guertin, A., Haddad, F., Michel, N. and Métivier, V., Cross section measurements of deuteron induced nuclear reactions on natural tungsten up to 34 MeV, Applied Radiation and Isotopes 97 (2015) 52-58. [7] Duchemin, C., Guertin, A., Haddad, F., Michel, N. and Métivier, V., Deuteron Induced Reactions on Ca-44 up to 34 MeV, submitted. [8] Koning, A.J., Rochman, D., 2012. Modern nuclear data evaluation with the TALYS code system, Nucl. Data Sheets 113, 2841.

Abstract IPHC_abstract_CDuchemin.pdf