A Radionuclide Generator of High-Purity Bi-213 for Instant Labeling

Abstract

A new two-column 225Ac/213Bi generator was developed specifically for using 225Ac containing an impurity of long lived 227Ac. The parent 225Ac was retained on the first Actinide Resin column, while 213Bi was accumulated on the second column filled with AG MP-50 resin via continuous elution and decay of intermediate 221Fr. The 213Bi accumulation was realized in circulation mode which allowed a compact generator design. It was demonstrated that 213Bi could be quickly and effectively extracted from AG MP-50 in form of complexes with various chelating agents including DTPA and DOTA. The performance of the generator presented and a conventional single-column generator on the base of AG MP-50 was tested and both generators were loaded with 225Ac containing 227Ac impurity. The 213Bi generation efficiencies were comparable and greater than 70%, whereas the developed generator provided a deeper degree of purification of 213Bi from Ac isotopes and decay products of 227Ac.

Targeted Alpha Therapy: All We Need to Know about 225Ac’s Physical Characteristics and Production as a Potential Theranostic Radionuclide

“…In order to produce the short-lived 213 Bi (T 1/2 = 45.6 min) on-site, 225 Ac can either be utilised directly as a therapeutic nuclide [50,106] or set onto 225 Ac/ 213 Bi generators [78,83]. All patient investigations with 213 Bi up to now have utilised 225 Ac/ 213 Bi generators.…”

Production of 225Ac for medical application from 232Th-metallic targets in Nb-shells irradiated with middle-energy protons

“…49 230 U can be used as a promising independent therapeutic radionuclide or as a source for a 230 U/ 226 Th generator. 50 The previously proposed methods for isolating 230 Pa and 223 Ra from an irradiated thorium target were designed considering that 225 Ac is the main product of thorium irradiation. 51,52 223 Ra is more efficiently produced by a different method, and 230 Pa has not yet found a real medical application.…”

“…5 225 Ac can be applied both directly and as a source of another a-emitter 213 Bi in medical generators. [6][7][8] The short-lived 213 Bi (t 1/2 = 46 min) is more preferable for the treatment of rapidly accessible types of cancer with fast pharmacokinetics. [9][10][11] Current clinical trials with 213 Bi-labeled compounds are conducted for leukemia, NHL, carcinoma, neuroendocrine tumors, glioma, etc.…”

Rapid EElution of ²²⁶Th from a Two-Column ²³⁰U/²²⁶Th Generator with Diluted and Buffer Solutions

“…Long-lived admixture makes the medical use of 230 U as a source in a radionuclide generator of 226 Th more prospective than direct applications. 226 Th is considered to be an alternative to another promising generator-produced short-lived radionuclide 213 Bi (T1/2 = 45.6 min) [20]. 226 Th provides a greater impact on cancer cells compared with 213 Bi.…”