Anion selective chromogenic and fluorogenic chemosensor and its application in breast cancer live cell imaging

A novel Schiff base receptor (L) bearing catechol and phenol groups was synthesized and characterized by various spectral (FTIR, 1H NMR and mass) data. The anion recognition ability of L was investigated by experimental (UV-Vis, fluorescence and 1H NMR) and theoretical (B3LYP/6-31G**) methods. Among the tested anions, the receptor L showed both naked-eye detectable color change from light-yellow to intense brownish-yellow and spectral (hyperchromic shift at 450 nm and ‘turn-on’ fluorescence at 480 nm) changes selectively towards F− and AcO− in DMSO and mixed DMSO–H2O medium because of the formation of a hydrogen bonded anion-receptor complex followed by the deprotonation of L. The receptor L was tested for live breast cancer cell imaging and can be applied to the breast tumour diagnosis.