Speaker
Description
Astatine‑211 (211At) is a high‑value alpha‑emitting radionuclide with significant potential for targeted alpha therapy. However, current production capacity remains insufficient to meet research and pre-clinical demand, limiting progress toward broader medical adoption. The dominant production route for 211At (t₁/₂ = 7.2 h) is the 209Bi (α,2n) 211At reaction using 28-29 MeV alpha irradiation of high‑purity bismuth targets. Metallic bismuth is commonly employed due to its favorable chemical properties, monoisotopic nature, and ability to be readily melted and cast into targets. The standard geometry is 90 microns thick and 25.4 mm diameter. Despite this, challenges in target robustness, thermal performance under high‑current irradiation, and efficient post‑irradiation recovery remain key barriers to in-creasing the production scale.
This work investigates improved bismuth target fabrication methods with an emphasis on the interface between the bismuth and aluminium target backing, which has been identified through experimentally benchmarked computational modeling and simulation to be a critical limiting factor for target performance. In addition to conventional melt‑casting, new approaches are being evaluated, including electrodeposition of bismuth layers to achieve enhanced uniformity, substrate compatibility, and performance under high‑power irradiation conditions. These advancements aim to support more efficient, scalable, and reliable 211At production for the nuclear medicine research community.