Crystalline Inorganic Anion Exchanger 188Re Generator

描述(由申请人提供)： 高能β(β)发射和短半衰期(16.9小时)使188Re成为放射治疗应用的优秀同位素。Re和Tc在化学行为上的相似性意味着，为99mTc开发的成像方案可以直接转换为188Re的治疗方案。不幸的是，Re作为一种治疗剂的半衰期很短，这使得它不可能从中央来源供应。目前的发电机不足以在终端用户现场可靠地提供纯188Re。该项目的目的是开发一种更好的188Re发生器系统，延长运行寿命，以降低成本并提高终端用户获得放射性同位素的能力。正在考虑的晶态无机化合物是层状铝混合氢氧化物，它可以作为阴离子交换剂合成。理想的化合物强烈保留二价钨酸盐(WO4=)，而不保留一价高铁酸根(ReO4-)。在测试了一系列镁和锂铝酸盐组合物后，组合物获得了高钨酸盐保留量(KD&GT；1.8)。10[6]用于mg和&gt；8。10[4]用于Li)。根据平衡测试，这些组分的WO4=/ReO4-分离因子分别为18000和500。这些组合物被造粒(&lt；300微米)，用于生产小型发电机，测试发现，这些发电机可靠地提供完全不含188W的188Re，显示出比平衡测试中看到的更大的分离系数。该项目的第二阶段将包括改进离子交换器的造粒和交换动力学，最终将基于这一技术制造和测试全尺寸发电机。该项目的最终目标是一种商业上可行的188Re发生器，用于医院、放射性药物和为多家医院提供服务的地区性放射性药物等终端设施。这将提高188Re作为放射免疫治疗(RIT)和类似技术的活性成分的可用性。

DESCRIPTION (provided by applicant): A high-energy beta (beta-) emission and short half life (16.9 hr) makes 188Re an excellent isotope for radiotherapeutic applications. The similarity in the chemical behavior of Re and Tc means that imaging [protocols developed for 99mTc can be directly converted to therapeutic protocols for 188Re. Unfortunately the short half-life that makes Re attractive as a therapeutic agent makes it impossible to supply from a central source. Current generators are not adequate for the reliable delivery of pure 188Re at the end user site. The aim of this project is to develop a superior generator system for 188Re with an increased operating life to reduce the cost and improve the availability of the radioisotope to end-users. Crystalline inorganic compounds under consideration are layered aluminum mixed hydroxides, which can be synthesized as anion exchangers. The ideal compound strongly retains divalent tungstate (WO4 =) but not monovalent perrhenate (ReO4-). After testing a range of compositions for both magnesium and lithium aluminates compositions were entitled with high tungstate retentions (Kd >1.8 . 10[6] for Mg and >8 . 10[4] for Li). Based on equilibrium tests, these compositions had WO4=/ReO4 - separation factors of 18,000 and 500 respectively. The compositions were pelletized (<300 mu m) and used to produce small generators, which were tested and found to reliably deliver 188Re completely free of 188W, demonstrating separation factors greater than those seen in the equilibration tests. Phase II of this project will include improved pelletization and exchange kinetics for the ion exchangers and will culminate in the fabrication and testing of full size generators based on this technology. The ultimate goal of this project is a commercially viable 188Re generator for use in end use facilities such as hospitals, radiopharmacies, and regional radiopharmacies serving multiple hospitals. This will improve the availability of 188Re for use as the active component for radioimmunotherapy (RIT) and similar techniques.