Coumarin based hydrazone as an ICT-based fluorescence chemosensor for the detection of Cu2+ ions and the application in HeLa cells.

We have constructed a new coumarin based fluorescence probe BENZPYR with ICT character through condensation of N, N-diethylamino-3-acetyl coumarin with 2-hydrazinobenzothiazole. The absorbance and fluorescence spectral characteristics of BENZPYR revealed that the chemosensor can specifically detect for Cu2+ ions over other different metal ions and the lowest limit of detection was found in nano molar range. The turn off sensor of BENZPYR is related to chelation enhanced quenching (CHEQ) and intramolecular charge transfer (ICT) processes were serve as excellent fluorescent detection of Cu2+ ions in DMF medium. Fluorescence microscopy experiments revealed that probe BENZPYR may have application as a fluorophore to detect the Cu2+ in living cells. The simulated DFT analysis of electronic and structural properties and also UV-vis absorption spectra are in well accordance with the experimental UV-vis absorption spectra.