A novel Bodipy-Dipyrrin fluorescent probe: Synthesis and recognition behaviour towards Fe (II) and Zn (II)

We present the design, synthesis, characterization and spectral studies for a new Zn (II) and Fe (II) selective fluorescent probe, 4,4-Difluoro-8-{3-[(4-phenoxy-dipyrromethene)propoxy]}-4-bora-3a,4a-diazaindacene (DPYBODPY). DPBODPY consists of a terminal fluorophore and a selective ligand and was designed to detect significant changes in absorbance and/or fluorescence on metal ion binding. The fluorophore is based on the Bodipy unit due to its excellent photophysical properties, while the dipyrrin unit has specific recognition abilities for Fe2+ and Zn2+ ions. The combination of these two structures is optimised to achieve significant spectral changes in the presence of Fe2+ and Zn2+ ions.

► A novel fluorescent sensor was synthesized and characterised.
► The ability of the new sensor to discriminate between metal cations was investigated.
► The novel sensor was shown to selectively recognize Fe (II) and Zn (II) cations.
► Stoichiometry and binding constants for metal complexes of the sensor were determined.
► Competition experiments indicate the sensor can discriminate between mixtures of metal ions.