This project will build on the work done in the Distinctive consortium, where it was shown that phosphate functionalised paramagnetic iron oxide particles showed a surprisingly large capacity and selectivity for uranium sorption. A first set of research objectives is to clarify further why what appears to be a multi-layer structure has such a large capacity. A second objective is to widen the same approach to other radionuclides of interest. A third objective is to develop particles that can act in acidic environments.