Abel E Paige, Domnanich Katharina, Clause Hannah K, Kalman Colton, Walker Wes, Shusterman Jennifer A, Greene John, Gott Matthew, Severin Gregory W
Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States.
National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, United States.
ACS Omega. 2020 Oct 22;5(43):27864-27872. doi: 10.1021/acsomega.0c03020. eCollection 2020 Nov 3.
An experiment was performed at the National Superconducting Cyclotron Laboratory using a 140 MeV/nucleon Ca beam and a flowing-water target to produce Ca for the first time with this production route. A production rate of 0.020 ± 0.004 Ca nuclei per incoming beam particle was measured. An isotope harvesting system attached to the target was used to collect radioactive cationic products, including Ca, from the water on a cation-exchange resin. The Ca collected was purified using three separation methods optimized for this work: (1) DGA extraction chromatography resin with HNO and HCl, (2) AG MP-50 cation-exchange resin with an increasing concentration gradient of HCl, and (3) AG MP-50 cation-exchange resin with a methanolic HCl gradient. These methods resulted in ≥99 ± 2% separation yield of Ca with 100% radionuclidic purity within the limits of detection for HPGe measurements. Inductively coupled plasma-optical emission spectrometry (ICP-OES) was used to identify low levels of stable ions in the water of the isotope harvesting system during the irradiation and in the final purified solution of Ca. For the first time, this experiment demonstrated the feasibility of the production, collection, and purification of Ca through isotope harvesting for the generation of Sc for nuclear medicine applications.
在美国国家超导回旋加速器实验室进行了一项实验，使用能量为140 MeV/核子的钙束和流水靶，首次通过这种生产途径制备钙。测得的生产率为每入射束粒子产生0.020±0.004个钙核。连接到靶上的同位素收集系统用于从水中的阳离子交换树脂上收集包括钙在内的放射性阳离子产物。收集到的钙使用针对这项工作优化的三种分离方法进行纯化：（1）用硝酸和盐酸的二甘醇酰胺萃取色谱树脂；（2）盐酸浓度梯度递增的AG MP-50阳离子交换树脂；（3）甲醇盐酸梯度的AG MP-50阳离子交换树脂。这些方法在高纯锗测量的检测限范围内，实现了钙的分离产率≥99±2%，放射性核纯度为100%。电感耦合等离子体发射光谱法（ICP-OES）用于识别辐照期间同位素收集系统的水中以及最终纯化的钙溶液中的低水平稳定离子。该实验首次证明了通过同位素收集制备、收集和纯化钙以用于核医学应用中钪的生成的可行性。
