A novel naphthalimide-derived “turn-off” chemosensor for the detection of Cu2+, F- and CN- ions

Abstract

The development of selective chemosensor for the detection of detrimental analytes in the environment is crucial due to their catastrophic effects. In this study, a novel Schiff base derived from naphthalimide and salicylaldehyde was designed and prepared for the detection of Cu2+, F-, and CN- ions in CH3CN as medium. The chemosensor exhibits a red shift in the presence of Cu2+, F-, and CN- ions accompanied by naked eye color change in the presence of F- and CN- ions. On the other hand, a “turn-off” response was observed in the presence of ion Cu2+, F-, and CN- ions in the fluorescent spectrum. The good anti-interference characteristics, strong binding, and low limit of detection (LOD) of the chemosensor revealed its sensitivity against Cu2+, F-, and CN- ions i.e. 1.25 × 10-5 M, 1.07 × 10-6 M, and 0.98 × 10-6 M, respectively. The binding ratio (1:1) was determined by Job's plot between the chemosensor and ions. In addition, the binding of ions with the chemosensor was proposed which was further supported by time-dependent density functional theory (TD-DFT) and IR spectrum data.