The present invention provides a method for generating a purified solution of at least one alpha-emitting radionuclide complex. The method comprises contacting a solution of the alpha-emitting radionuclide complex and at least one daughter nuclide with at least one selective binder for the daughter nuclide and subsequently separating the solution from the selective binder. The invention also provides a method for the removal of at least one daughter radionuclide from a solution comprising at least one alpha-emitting radionuclide complex. The method comprises contacting the solution with at least one selective binder for the daughter nuclide.