Novel probes for selective fluorometric sensing of Fe(II) and Fe(III) based on BODIPY dyes

Abstract

Two novel boron-dipyrromethene (BODIPY) based fluorescence turn-off sensors, which demonstrate high selectivity and sensitivity toward Fe 2+ and Fe 3+ ions have been reported. A simple and high yielded synthesis of fluorescent BODIPY derivatives with malonyl unit for sensitization have been described. This approach provides quick, high yielded and low-cost preparation of probes. The two sensors have been comprised of combination of one and two BODIPY fluorophore and a malonyl unit, substituted on meso position of BODIPYs. Synthesized BODIPY derivatives have been characterized via elemental analyses, mass spectrometry, 1 H and 13 C spectroscopy and their photophyisical properties were investigated by UV- Vis absorption and fluorescence emission spectroscopy.  The synthesized sensors ( 2, 3 ) have been used as a fluorescent probe towards the selective and sensitive detection of biologically important Fe 2+ and Fe 3+ ions in tetrahydrofuran by fluorescence spectroscopy. The limit of detection (LOD) have been calculated to be for the BODIPY 2 , 14.61 (Fe 2+ ), 1.22 (Fe 3+ ) and for BODIPY 3 , 1.16 (Fe 2+ ) and 1.06 (Fe 3+ ).