Journal Article

Production and purification of molecular 225 Ac at CERN-ISOLDE

Schweiger, Ch, Düllmann, Ch E, Wienholtz, F, Rothe, S, Fischer, P, Stegemann, S, Athanasakis-Kaklamanakis, M, Au, M, Cocolios, T E, Reilly, J, Nies, L, Köster, U, Wojtaczka, W, Mougeot, M, Giesel, P F, Schweikhard, L, Lange, D, Schlaich, M, Johnson, J D

2025

Overview

The radioactive nuclide Ac is one of the few promising candidates for cancer treatment by targeted- -therapy, but worldwide production of Ac faces significant limitations. In this work, the Isotope Separation On-Line method was used to produce actinium by irradiating targets made of uranium carbide and thorium carbide with 1.4-GeV protons. Actinium fluoride molecules were formed, ionized through electron impact, then extracted and mass-separated as a beam of molecular ions. The composition of the mass-selected ion beam was verified using time-of-flight mass spectrometry, - and -ray decay spectrometry. Extracted quantities of particles per C of incident protons were from a uranium carbide target and for a thorium carbide target. Using a magnetic mass separator, the long-lived contamination Ac is suppressed to (95% confidence interval) with respect to Ac by activity. Measured rates scale to collections of 108 kBq A h of directly produced .