A Novel Colorimetric and “Turn-On” Fluorescent Sensor for Selective Detection of Cu2+

In this work, a new highly selective and sensitive fluorescent sensor for detecting Cu2+ was developed based on rhodamine fluorophore. It displayed strong fluorescence “turn-on” effect upon addition of Cu2+, and possessed the function of naked eye recognition. The fluorescence enhancement also enabled the sensor to quantitatively analyze Cu2+ due to the formation of a stable 1:1 metal–ligand complex in a short time, and the complex possesses relatively good pH stability. In addition, the density functional theory calculations were adopted to investigate the molecular orbitals as well as the spatial structure. Simultaneously, the cell imaging and zebra fish experiments provided a broader application prospect in biological system.