Bioimaging application of a novel anion selective chemosensor derived from vitamin B6 cofactor

The detection of intracellular fluoride was achieved by a novel Schiff base chemosensor derived from vitamin B6 cofactor (L) using fluorescence imaging technique. The sensor L was synthesized by condensation of pyridoxal phosphate with 2-aminothiophenol. The anion recognition ability of L was explored by UV-Vis and fluorescence methods in DMSO and mixed DMSO-H2O system. The sensor L showed both naked-eye detectable color change from colorless to light green and remarkable fluorescence enhancement at 500 nm in the presence of F(-) and AcO(-). The anion recognition was occurred through the formation of hydrogen bonded complexes between these anions and L, followed by the partial deprotonation of L. The detection limit of L for the analysis of F(-) and AcO(-) was calculated to be 1.88 μM and 9.10 μM, respectively. Finally, the detection of cytoplasmic fluoride was tested using human cancer cell HeLa through fluorescence imaging.