A Highly Selective Colorimetric and Off-on-off Fluorescent Probe for Fluoride Ions

In this paper. a highly selective and sensitive probe for fluoride ions (F-), containing a phenylpyridylvinylene derivative reporter and a Si-O bond receptor, was designed and characterized. The reaction MU:mechanism is based on the intramolecular charge transfer (ICT) mechanism. Upon addition of F-. probe 1 showed a remarkable red-shift (183 nm) in the absorption spectra accompanying with the color changes from colorless to purple. so probe 1 could serve as a naked-eye probe for F-. The absorbance of probe 1 at 545 nm increased linearly with the concentration of F- from 20 to 150 mu M The detection limit was calculated to be 0.1 mu M. Besides, off-on-off fluorescence intensity changes were also observed in the fluorescence spectra. The present results may provide a useful approach for the development of highly selective dual-channel probes for F-.