Radiochemical separation and purification of promethium-149 radioisotope from irradiated of neodymium oxide target (98.4% of ¹⁴⁸Nd enrichment) based on extraction chromatography method

Cancer is the second leading cause of death globally and increasing every year, including in Indonesia. Promethium-149 (¹⁴⁹Pm) is one of beta-emitting (E_β-max of 1.07 MeV and T_1/2 of 2.21 days) radiolanthanides that can be used for therapeutic application. Radioisotope of ¹⁴⁹Pm can be produced with high specific activity that was suitable for labeling of biomolecule as a targeted radiopharmaceutical for cancer therapy. Radiochemical separation of ¹⁴⁹Pm from irradiated of neodymium oxide (Nd₂O₃) target with 98.4% neodymium-148 (¹⁴⁸Nd) isotope enrichment has been carried out based on extraction chromatography method using LN (Eichrom) resin column. The target material was irradiated at Bandung TRIGA 2000 reactor. Radiochemical purity the final product of ¹⁴⁹PmCl₃ radioisotope was determined using paper chromatography and paper electrophoresis methods. Radionuclide purity of ¹⁴⁹PmCl₃ solution was determined using a gamma-ray spectrometer equipped with HP-Ge detector and a multichannel analyzer (MCA). The results show that the optimum condition on separation of ¹⁴⁹Pm from irradiated of Nd₂O₃ target with 98.4% ¹⁴⁸Nd isotope enrichment was obtained using 1.5N HNO₃ solution at temperature of 80 °C as mobile phase. The yield of ¹⁴⁹Pm obtained from the separation was 97.8 ± 2.1%. The final product of 149PmCl₃ radioisotope has physico-chemical characteristic that meet the requirements for nuclear medicine applications with radiochemical purity and radionuclide purity of 99.7 ± 0.2% and 99.9 ± 0.1%, respectively. The solution of ¹⁴⁹PmCl₃ was clear, with the pH of 1 and stable for 1.5 weeks at room temperature.