Large-Scale Production of Te and Sb for Radiopharmaceutical Applications.

Radionuclides find widespread use in medical technologies for treating and diagnosing disease. Among successful and emerging radiotherapeutics, Sb has unique potential in targeted therapeutic applications for low-energy electron-emitting isotopes. Unfortunately, developing Sb-based drugs has been slow in comparison to other radionuclides, primarily due to limited accessibility. Herein is a production method that overcomes this challenge and expands the available time for large-scale distribution and use. Our approach exploits high flux and fluence from high-energy proton sources to produce longer lived Te. This parent isotope slowly decays to Sb, which in turn provides access to Sb for longer time periods (in comparison to direct Sb production routes). We contribute the target design, irradiation conditions, and a rapid procedure for isolating the Te/Sb pair. To guide process development and to understand why the procedure was successful, we characterized the Te/Sb separation using Te and Sb K-edge X-ray absorption spectroscopy. The procedure provides low-volume aqueous solutions that have high Te-and consequently Sb-specific activity in a chemically pure form. This procedure has been demonstrated at large-scale (production-sized, Ci quantities), and the product has potential to meet stringent Food and Drug Administration requirements for a Te/Sb active pharmaceutical ingredient.