A dicyanisophorone based fluorescent probe for naked–eye recognition and near–infrared fluorescence detection of palladium

The eco–environmental toxicity of the rare metal palladium (Pd) has received extensive attention, thereby requiring simple and practical methods for detecting Pd. Herein, a new probe (HPD) based on dicyanoisophorone dye was designed and synthesized for the detection of Pd. HPD provides several advantages for tracking Pd, including near–infrared (NIR) emission (λex = 670 nm, λem = 700 nm), naked–eye recognition, and comprehensive detection of 0/2/4 valence Pd with good selectivity and anti–interference. The reaction–sensing mechanism of HPD for Pd was further studied using density functional theory calculations. HPD was demonstrated to be a promising tool for the detection of Pd in real water samples, as well as the imaging of Pd in living cells and animals. [Display omitted] •A novel intramolecular charge transfer (ICT) based fluorescence probe was developed to detect palladium (Pd).•Near–infrared (NIR) emission and naked–eye detection of Pd are performed.•The detection mechanism of the probe was verified by experiments and calculations.•The probe can detect Pd in real water samples, living cells and animals.