Zalutsky Michael R, Pruszynski Marek
Department of Radiology, Duke University Medical Center, Durham, NC 27710 USA.
Curr Radiopharm. 2011 Jul;4(3):177-85. doi: 10.2174/1874471011104030177.
The 7.2-h half life radiohalogen (211)At offers many potential advantages for targeted α-particle therapy; however, its use for this purpose is constrained by its limited availability. Astatine-211 can be produced in reasonable yield from natural bismuth targets via the (209)Bi(α,2n)(211)At nuclear reaction utilizing straightforward methods. There is some debate as to the best incident α-particle energy for maximizing 211At production while minimizing production of (210)At, which is problematic because of its 138.4-day half life α-particle emitting daughter, (210)Po. The intrinsic cost for producing (211)At is reasonably modest and comparable to that of commercially available (123)I. The major impediment to (211)At availability is attributed to the need for a medium energy α-particle beam for its production. On the other hand, there are about 30 cyclotrons in the world that have the beam characteristics required for (211)At production.
半衰期为7.2小时的放射性卤素砹-211为靶向α粒子治疗提供了许多潜在优势;然而,其在该用途上的应用受到其可得性有限的限制。通过使用简单方法的(209)Bi(α,2n)(211)At核反应,可从天然铋靶以合理产率制备砹-211。关于使211At产量最大化同时使210At产量最小化的最佳入射α粒子能量存在一些争议,210At存在问题,因为其半衰期为138.4天的α粒子发射子体(210)Po。制备(211)At的固有成本相当适中,与市售(123)I相当。(211)At可得性的主要障碍归因于其生产需要中能α粒子束。另一方面,世界上约有30台回旋加速器具备生产(211)At所需的束流特性。