Spine metastases are a common and painful complication of cancer. A novel concept of treatment combines the in situ vertebroplasty with radiotherapy employing radioactive bone cement into the human vertebrae. Thus, investigations concerning possible bioactive and radioactive cements become a relevant theme. In this work, we have synthesized calcium phosphate bioceramics incorporated with Ho and Sm nuclides using sol-gel technique. Characterizations were performed using X-ray diffractometry, infrared spectroscopy, scanning electron microscopy, instrumental neutron activation analysis, and gamma spectroscopy. Results showed bioceramics composed by multiphasic calcium phosphates along with holmium and samarium phosphates, with 8.9 and 13.7 % of Sm and Ho in weight, respectively. After neutron activation, the Ho-166 and Sm-153 beta-emitters were identified and quantified on the bioceramics with activities estimated at 32.5 and 14.5 MBq/mg of Sm-153 and Ho-166 bioceramic powder, respectively. These radioactive calcium phosphate bioceramics can compose suitable radioactive cements to radiovertebroplasty.

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This work studied the effects of β radiation of

Ceramic seeds were synthesized by the sol-gel technique with Si:Sm:Ca. One sample was irradiated in the TRIGA nuclear reactor IPR-R1. After irradiation, the seeds were submitted to instrumental neutron activation analysis to determine the 153 Sm concentration in weight. The same irradiated seed sample was submitted to gamma spectrometry analysis to determine all existing radionuclides as well as its individual activities. A second sample was submitted to ICP-AES atomic emission spectrometry. A third sample was submitted to X-ray fluorescence spectrometry to determine qualitative chemical composition. The measured activity was due to 153 Sm with a wellcharacterized gamma spectrum. The X-ray fluorescence spectrum demonstrates that there is no discrepancy in seed composition. Maximum range of beta particles from 153 Sm were evaluated, as well as the total dose and dose rate on its range´s volume. The results are relevant for investigation of the viability of producing 153 Sm radioactive seeds for use in brachytherapy.