A new "turn-on" fluorescent chemosensor for Zn2+ based on a diarylethene derivative and its practical applications

A new photochromic fluorescent chemosensor 1o based on a diarylethene derivative was designed and successfully synthesized. In this work, 1o acted as a "turn-on" fluorescence sensor for detecting Zn2+ in methanol solution with the characteristics of fast response, good sensitivity and high selectivity over other metal ions. Compared with the initial fluorescence emission peak of 1o, upon the addition of Zn2+, a new strong fluorescence emission peak centered at 582 nm appeared with a significant intensity enhancement (105-fold), and the fluorescent color of the 1o solution changed from darkness to bright yellow. The results of Job's plot and HFtMS determined the binding stoichiometry of 1:1 between 1o and Zn2+. Besides, the limit of detection (LOD) of 1o towards Zn2+ was calculated at very low concentration up to 13.4 nM. Moreover, the fluorescence signals of 1o were used to design a logic gate. Furthermore, 1o could also detect trace amounts of Zn2+ in real water samples, suggesting the practical application in environmental systems.