%0 Journal Article
%T Production, quality control and bodistribution studies of labeled (ethylenediamine tetra (methylene phosphonic acid) with thulium-170.
%A Simindokht Shirvani-Arani
%A Ali Bahrami-Samani
%A Amir Reza Jalilian
%A Mohammad Ghannadi Maragheh
%J Iranian Journal of Nuclear Medicine
%D 2010
%I 
%X Introduction: Thulium-170 [T1/2=128.4 days, E¦Â(max)=968 keV, E¦Ã=84 keV (3.26%)] has radionuclidic properties suitable to be used -in combination with phosphonic compound such Ethylenediamine tetra (methylene phosphonic acid) (EDTMP)- in palliative therapy of bone metastases as an alternative to 89SrCl2. In the case of thulium-170, requirement for an enriched target does not arise and radionuclidic impurities are not formed by radiative capture during neutron activation. Methods: In this study 170Tm was produced using Tm (NO3)3, prepared by neutron activation (3-4 ¡Á 1013) of a natural sample with a radio-nuclidic purity of >99.99% (RTCL, DTPA 1mM and Whatman3MM as stationary phase). EDTMP was synthesized by following a Mannich-type reaction and radiolabeled with 170Tm. Complexation parameters were optimized to achieve maximum yields (>99%). The Radiochemical purity of 170Tm-EDTMP was checked by RTLC and ITLC. It was found to retain its stability at room temperature even after 2 months of preparation (> 95%). Biodistribution studies carried out in wild-type rats for both free 170Tm cation and the complexed ion with EDTMP. Results: It was observed that complexation gradually increased with increase in ligand concentration and reached to ~ 100% at a ratio of [ligand]/[metal] ~ 20:1. The in vitro stability studies were performed by incubating the complex at room temperature and showed that the radiochemical purity of the complex remained >95% up to 2 month after preparation. A volume of 50-100 ml containing 180¡À5 mCi of radioactivity was injected through a lateral tail vein. The animals were sacrificed at the exact intervals of 2, 4, 24 and 48 h, and one and two month post injection. Based on these results, it was concluded that the major portion of injected activity was extracted from blood circulation into bones. Serial scintigraphic images were recorded at 2h, 4h, 24h and 48h post injection (pi) for free 170Tm and also at 2h, 48h and 1w pi for 170Tm-EDTMP injected to the rats, by a single-head SPECT system (Siemens) based on 84 keV peak. Conclusion: The produced 170Tm-EDTMP properties suggest applying a new efficient bone pain palliative therapeutic agent in the country instead of some other in use radiopharmaceuticals, such as 89SrCl2 and 32P, in order to overcome the metastatic bone pains
%K Thulium-170
%K Bone pain
%K Palliatives
%K EDTMP
%U http://journals.tums.ac.ir/PdfMed.aspx?pdf_med=/upload_files/pdf/16974.pdf&manuscript_id=16974