Selective Recognition of Fe(III) in Aqueous Environment over Covalently-Bonded Tb-Complex-Containing Fluorescent Porous Copolymer Microspheres

An environment-friendly synthesis of a covalently bonded terbium(Tb)-complex-containing monodispersed fluorescent porous copolymer microspheres, and their highly selective detection of Fe3+ are described. The as-made copolymer microspheres exhibit intense green fluorescence originating from Tb ions and high photostability in water. Encouragingly, the fluorescence of the copolymer microspheres can be selectively quenched by trace Fe3+ due to the interaction between Fe3+ and the ligands, which disturbs the coordination structure of Tb-complexes and inhibits the energy transfer from ligands to Tb ions. The intense fluorescence intensity, high fluorescence stability, together with the nanoscale and porous nature of the copolymer microsphere endows them with wide detection range (0-1500 mu m) and low detection limit (2.1 mu m) for selective recognition of Fe3+ in aqueous environment. This study paves a new pathway for the function of porous copolymer microspheres being used as targeting for biological detection and environmental issues.