Colorimetric as well as dual switching fluorescence ‘turn on’ chemosensors for exclusive recognition of Zn2+ and in aqueous solution: experimental and theoretical studies

In this Letter, we have designed and synthesized two salicylaldehyde based probes (DPSH and ANSH) which selectively detect Zn2+ and HSO 4 - over other physiologically and environmentally important ions with a fluorescence enhancement at two different wavelengths in aqueous acetonitrile solution. The binding mode and change of electronic properties of DPSH and ANSH with Zn2+ and HSO 4 - were modeled by DFT (density functional theory) and TDDFT (time dependent density functional theory) computational calculations, respectively. The minimum limits of detection (LOD) of the sensors with both cases were in the order of 10−8 M each.