Hevesy Laboratory, Center for Nuclear Technologies, Technical University of Denmark, Roskilde, Denmark.
Phys Med Biol. 2017 Dec 29;63(1):015026. doi: 10.1088/1361-6560/aa9b44.
La has favorable nuclear and chemical properties for Auger-based targeted internal radiotherapy. Here we present detailed investigations of the production, emissions, and dosimetry related to La therapy. La was produced by 16.5 MeV proton irradiation of metallic Ba on a medical cyclotron, and was isolated and purified by trap-and-release on weak cation-exchange resin. The average production rate was 407 ± 19 MBq µA (saturation activity), and the radionuclidic purity was 98% at 20 h post irradiation. Chemical separation recovered > 98 % of the La with an effective molar activity of 70 ± 20 GBq µmol. To better assess cellular and organ dosimetry of this nuclide, we have calculated the x-ray and Auger emission spectra using a Monte Carlo model accounting for effects of multiple vacancies during the Auger cascade. The generated Auger spectrum was used to calculate cellular S-factors. La was produced with high specific activity, reactivity, radionuclidic purity, and yield. The emission spectrum and the dosimetry are favorable for internal radionuclide therapy.
镧具有适合基于俄歇电子的靶向内放射治疗的核和化学性质。在这里，我们对镧治疗相关的生产、排放和剂量学进行了详细的研究。镧通过在医用回旋加速器上用 16.5 MeV 质子辐照金属钡来生产，并通过在弱阳离子交换树脂上的捕获和释放来分离和纯化。平均生产速率为 407 ± 19 MBq µA（饱和活性），辐照后 20 小时的放射性核纯度为 98%。化学分离回收了 > 98%的镧，有效摩尔活度为 70 ± 20 GBq µmol。为了更好地评估该核素的细胞和器官剂量学，我们使用蒙特卡罗模型计算了 X 射线和俄歇发射谱，该模型考虑了在俄歇级联过程中多个空位的影响。生成的俄歇谱用于计算细胞 S 因子。镧具有高比活度、反应性、放射性核纯度和产率。发射光谱和剂量学有利于内部放射性核素治疗。
