Background 161 Tb is an interesting radionuclide for cancer treatment, showing similar decay characteristics and chemical behavior to clinically-employed 177 Lu. The therapeutic effect of 161 Tb, however, may be enhanced due to the co-emission of a larger number of conversion and Auger electrons as compared to 177 Lu. The aim of this study was to produce 161 Tb from enriched 160 Gd targets in quantity and quality sufficient for first application in patients. Methods No-carrier-added 161 Tb was produced by neutron irradiation of enriched 160 Gd targets at nuclear research reactors. The 161 Tb purification method was developed with the use of cation exchange (Sykam resin) and extraction chromatography (LN3 resin), respectively. The resultant product ( 161 TbCl 3 ) was characterized and the 161 Tb purity compared with commercial 177 LuCl 3 . The purity of the final product ( 161 TbCl 3 ) was analyzed by means of γ-ray spectrometry (radionuclidic purity) and radio TLC (radiochemical purity). The radiolabeling yield of 161 Tb-DOTA was assessed over a two-week period post processing in order to observe the quality change of the obtained 161 Tb towards future clinical application. To understand how the possible drug products (peptides radiolabeled with 161 Tb) vary with time, stability of the clinically-applied somatostatin analogue DOTATOC, radiolabeled with 161 Tb, was investigated over a 24-h period. The radiolytic stability experiments were compared to those performed with 177 Lu-DOTATOC in order to investigate the possible influence of conversion and Auger electrons of 161 Tb on peptide disintegration. Results Irradiations of enriched 160 Gd targets yielded 6–20 GBq 161 Tb. The final product was obtained at an activity concentration of 11–21 MBq/μL with ≥99% radionuclidic and radiochemical purity. The DOTA chelator was radiolabeled with 161 Tb or 177 Lu at the molar activity deemed useful for clinical application, even at the two-week time point after end of chemical separation. DOTATOC, radiolabeled with either 161 Tb or 177 Lu, was stable over 24 h in the presence of a stabilizer. Conclusions In this study, it was shown that 161 Tb can be produced in hig...

UO 2 samples doped with 6, 11, 22 mol% lanthanum were examined before and after air oxidation. To verify the formation of uranium-lanthanum-mixed oxide solid solutions, powder X-ray diffraction (XRD) analyses of the crystalline phases in the materials were carried out. The presence of oxygen vacancies in the La-doped UO 2 samples was identified by Raman spectrometry. It was evidenced by changes induced in the Raman spectra by air oxidation. This latter was carried out either by increasing the Raman laser power or by thermally treating the samples at 500 K for 370 h. In addition, oxidation behavior differences of pure and La-doped UO 2 samples were reported by comparing XRD and Raman results of the samples before and after air oxidation. It was shown that the concentration of the M 4 O 9 (M: U, La) phase increased with increasing content of La, whereas inhibition for the formation of M 3 O 8 phase was observed.

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