Yolk-Shell Pst@SiO2 decorated with functional guests: A new solid-phase extractant for highly effective separation of no carrier added 177Lu

With the rapid development of ¹⁷⁷Lu-related radiopharmaceuticals, there is an urgent need for large-scale production of ¹⁷⁷Lu efficiently. In this work, we employed yolk-shell Pst@SiO₂ to accommodate 2-ethylhexyl 2-ethylhexylphosphonic acid (HEH[EHP]), obtaining a material with ideal microstructure and adequate functionality to isolate Lu from Yb effectively. ¹⁷⁷Lu isolation on HEH[EHP]-Pst@SiO₂ dynamic column has been demonstrated to be influenced by various parameters such as the initial target solution, the eluent property, and the separation temperature. Most importantly, an effective separation process including primary separation and secondary purification has been established based on plenty of simulated experiments and radioactively tracing investigations. As a result, NCA ¹⁷⁷Lu with high radionuclide and radiochemical purity (≥99.99 %) and excellent decontamination factor (10⁴) from Yb can be acquired in good recovery (>60%). This work provides not only a candidate for NCA ¹⁷⁷Lu production but also some important hints for the separation of other heavy lanthanides.