Development of neutron-activated samarium-153-loaded polystyrene microspheres as a potential theranostic agent for hepatic radioembolization

• Main Authors: Tan, Hun Yee, Wong, Yin How, Kasbollah, Azahari, Shah, Mohammad Nazri Md, Abdullah, Basri Johan Jeet, Perkins, Alan Christopher, Yeong, Chai Hong
• Format: Article
• Published: Lippincott Williams & Wilkins 2022
• Subjects: R Medicine; R Medicine (General); Medical technology
• Online Access: http://eprints.um.edu.my/32737/

Purpose Hepatic radioembolization is an effective minimally invasive treatment for primary and metastatic liver cancers. Yttrium-90 Y-90]-labelled resin or glass beads are typically used as the radioembolic agent for this treatment; however. these are not readily available in many countries. In this study, novel samarium-153 oxide-loaded polystyrene (Sm-153]Sm2O3-PS) microspheres were developed as a potential alternative to Y-90 microspheres for hepatic radioembolization. Methods The Sm-152]Sm2O3-PS microspheres were synthesized using solid-in-oil-in-water solvent evaporation. The microspheres underwent neutron activation using a 1 MW open-pool research reactor to produce radioactive Sm-153]Sm2O3-PS microspheres via Sm-152(n,gamma)Sm-153 reaction. Physicochemical characterization, gamma spectroscopy and in-vitro radionuclide retention efficiency were carried out to evaluate the properties and stability of the microspheres before and after neutron activation. Results The Sm-153]Sm2O3-PS microspheres achieved specific activity of 5.04 +/- 0.52 GBq.g(-1) after a 6 h neutron activation. Scanning electron microscopy and particle size analysis showed that the microspheres remained spherical with an average diameter of similar to 33 mu m before and after neutron activation. No long half-life radionuclide and elemental impurities were found in the samples. The radionuclide retention efficiencies of the Sm-153] Sm2O3-PS microspheres at 550 h were 99.64 +/- 0.07 and 98.76 +/- 1.10% when tested in saline solution and human blood plasma, respectively. Conclusions A neutron-activated Sm-153]Sm2O3-PS microsphere formulation was successfully developed for potential application as a theranostic agent for liver radioembolization. The microspheres achieved suitable physical properties for radioembolization and demonstrated high radionuclide retention efficiency in saline solution and human blood plasma. Copyright (C) 2022 Wolters Kluwer Health, Inc. All rights reserved.