Actinium 225 is a very important isotope for radiotherapy.
Much effort has gone into producing this isotope (Method For Producing Actinium-225 (2004)), separating it from other actinides (Systems, Apparatus And Methods For Separating Actinium, Radium, And Thorium (2019)) and developing complexes and antibodies to target cancer sites (Actinium-225 Complexes And Conjugates For Targeted Radiotherapy (2002), One-Step Labeling of Antibodies to High Specific Activity with Actinium-225 (2017)).
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All patent information has been obtained from Espacenet (European Patent Office).