[en] In this work, we studied the sorption of scandium, whose isotopes ⁴⁴Sc and ⁴⁷Sc are studied for diagnostics and therapy in nuclear medicine, by aggregates of commercial (TAN, STP) and oxidized ND nanodiamonds (ox-STP) from aqueous solutions. The sorption capacity of the studied NDs for scandium was determined; it was shown that 100 p.g of NDs is sufficient for the sorption of 1 GBq of ⁴⁷Sc, which is equivalent to the activity of isotopes used in therapy. It has been shown that the supposed mechanism for the binding of Sc(III) to ND aggregates is chemisorption, and the chemical composition of the ND surface affects the sorption efficiency to a greater extent than the forms of scandium in solution. The obtained data on Sc(III) sorption are compared with the sizes of ND aggregates; it is shown that sorption under experimental conditions does not depend on the size of the aggregates. Optimal carriers of the ⁴⁷Sc isotope have been found for further studies of radiopharmaceuticals based on it - TAN and ox-STP.

[en] Over the last few years, "4"7Sc has attracted significant attention for potential use in cancer theranostics due to its favorable nuclear decay characteristics (t_1_/_2 = 3.35 d; average β energy, 162 keV; Eγ, 159 keV). No-carrier-added (NCA) "4"7Sc can be produced via the "4"6Ca(n,γ)→"4"7Sc reaction in a nuclear reactor. For this purpose, 1 mg of CaO (98 % enrichment of "4"6Ca) target was irradiated for 7 d at a flux of 1 × 10"1"4 n.cm"-"2.s"-"1 at the Dhruva reactor of our research centre. The irradiated target was dissolved in 5 ml of 1 M HCl inside a lead shielded facility. The resultant solution was evaporated to near dryness, reconstituted in 20 ml of 0.15 M lithium citrate solution and transferred to the electrochemical cell. The electrochemical separation involved selective amalgamation of Ca from Ca/Sc mixture into mercury-pool cathode. The influence of different experimental parameters (such as applied potential, pH of the electrolyte, time of electrolysis and amount of Ca"2"+ ions in the electrolyte) on the separation process was investigated and optimized for the quantitative electroamalgamation of Ca

[en] In this study, scandium-47 and yttrium-90 have been used as representatives of potential cytotoxic labels. Both isotopes have a high yield of energetic beta particles and half-lives of the same order as indium-111. In addition they are both members of Group III and so may be used as a base for chemical comparisons in the future with radiotoxic isotopes from other chemical groups

[en] This work spotlights on the rapid and effective separation method for the no-carrier-added (NCA) ⁴⁷Sc from natural irradiated Ti target using an anionic exchanger resin; AN-31 impregnated with 4-(2-Pyridylazo) resorcinol (PAR). The newly prepared resin (An-PAR) was characterized by FTIR and SEM. The Influence of pH on the distribution coefficients (K_d) of Sc(III) and Ti(IV) ions was investigated by batch technique and the results revealed that Ti(IV) ions are strongly adsorbed by AN-PAR rather than AN-31, while Sc(III) ions are weakly adsorbed on the both resin materials. The radiochemical separation of ⁴⁷Sc(III) from irradiated natural Ti target was successfully carried out, where the elution efficiency for ⁴⁷Sc reached 89 ± 1.5% with high radiochemical, radionuclidic and chemical purities. Our findings thus hold a great promise for the use of ⁴⁷Sc radioisotope in the preparation of radiopharmaceuticals for theranostics applications. (author)

[en] Production of radioactive scandium by irradiating natural titanium metal in Pakistan Research Reactor-1 was evaluated. The production rate of ⁴⁷Sc and other radioactive scandium was estimated. High specific activity ⁴⁷Sc can be produced by irradiating enriched ⁴⁷Ti in sufficient quantities needed for therapeutic applications. A new separation technique based on column chromatography was developed. Neutron irradiated titanium was dissolved in hydrofluoric acid, which was evaporated and taken in distilled water. The resulting solution was loaded on silica gel column. The radioactive scandium comes out first and the inactive titanium is removed with 2 M HCl. More than 95% radioactive scandium was recovered, while chemical impurity of titanium determined by optical emission spectroscopy was less than 0.01 μg/mL in final product. (author)

[en] To assess the capability of Kyoto University Research Reactor to supply the domestic needs of medical isotopes, its neutron flux has been fully characterized. The production rates of theranostics radionuclides ¹⁷⁷Lu (from ¹⁷⁶Lu (n, γ) ¹⁷⁷Lu), ¹⁷⁶Lu (n, γ) ^177mLu/¹⁷⁷Lu and ¹⁷⁶Yb (n, γ) ¹⁷⁷Yb⟶β^-(1.88hr)¹⁷⁷Lu reactions), and ⁴⁷Sc (from ⁴⁶Ca (n, γ) ⁴⁷Ca⟶β^-(4.54d)⁴⁷Sc and Ti (n, p) ⁴⁷Sc) were evaluated. The activity (per gram of target) of ⁴⁷Sc produced from Ti was found to be 10 times higher than that produced from Ca. Production of ¹⁷⁷Lu from the decay of its isomer ^177mLu was found to be produce less radioactive wastes than Yb route and can be used as a generator for long-time use. (author)

No abstract available

[en] We have developed a precise method for determining Sc in natural water samples by preconcentration neutron activation analysis (PNAA) using a carrier-free radioactive nuclide (⁴⁷Sc) as a yield tracer. The separation of Sc from natural water samples was performed by iron precipitation technique followed by an anion exchange method, which enables more than 88% of Sc recovery. Blank samples indicated that the blank contribution was not negligible for determining Sc in natural samples. As for a surface seawater sample, blank corrections in raw data (real amount + blank) were 58-65% and 29% for the use of the normal polyethylene sheet and the high purity sheet, respectively, for sealing samples in neutron activation. However, the corrected data showed a good agreement irrespective of the polyethylene sheets. Our surface seawater Sc data (0.23-0.34 ng/kg) were comparable or slightly higher than the previous data. On the other hand, the rainwater Sc data (2.49-3.05 ng/kg) were one order lower than the reported data. As for rainwater, we are confident that our data were more reliable than the reported data, because the reported data were considered to be susceptible to contamination. Although further studies are required, we believe our newly developed Sc determination technique could be applied to various natural water samples

[en] Formation of Sc radioisotopes under the irradiation of titanium of natural isotopic composition by bremsstrahlung photons with energies up to 55 MeV was studied. The yield of ⁴⁷Sc is 5·10⁵ Bq/μA h (g/cm²). Inevitable impurities are ⁴⁶Sc and ⁴⁸Sc (1.5% and 9.1% of ⁴⁷Sc radioactivity at EOB, respectively). ⁴⁷Sc was separated by extraction chromatography on a DGA resin in HNO₃ and HCl media. The separation procedure takes about 2 h, the radiochemical efficiency was > 97%. The result was compared with other photonuclear experiments on titanium nuclei. It is shown that the photonuclear method can be used for the production of therapeutic amounts of ⁴⁷Sc. (author)

[en] A procedure is outlined for measuring calcium and titanium from ⁴⁷Sc by instrumental neutron activation analysis. Precise calcium measurements obtained from ⁴⁷Sc are compared with measurements based on ⁴⁷Ca and ⁴⁹Ca. The method is particularly suitable for low levels (ca. 1%) of calcium. (Auth.)