Isolation of Medicine-Applicable Actinium-225 from Thorium Targets Irradiated by Medium-Energy Protons

Abstract

A method of isolation of actinium-225 for nuclear medical applications from thorium targets irradiated by protons is presented. It comprises liquid extraction and extraction chromatography separations. The method demonstrates high (> 85%) chemical yield and radionuclide purity of the final product. An impurity of 227Ac (0.1% at the end of bombardment) does not hinder 225Ac from being used for medical 225Ac/213Bi generators.