Clickable complexing agents: functional crown ethers for immobilisation onto polymers and magnetic nanoparticles

Crown ethers and monoazacrown ethers supported onto well defined cobalt and Fe3O4 magnetic nanoparticles have been prepared and used as magnetically recoverable extracting materials for Pb2+ from aqueous and organic solutions. The assembly of the functional nanoparticles involves the integration of the complexing units by means of a copper-pcatalysed alkyne-pazide cycloaddition reaction leading to a 1,2,3-ptriazole linker. The same binding motifs have been also used to functionalise polystyrene (PS) and polystyrene-ppolyethyleneglycol (PS-pPEG) resins, and the resulting materials were also employed in the removal of Pb2+ from solutions. The relative merits of these two approaches are compared.