A diarylethene-based fluorescent chemosensor for highly selective recognition of Zn2+ and its application

A new diarylethene-based fluorescent chemosensor (1o) for highly selective recognition of Zn2+ was synthesized. The good photochromic response of 1o was found by alternately irradiating UV and visible light. Under the excitation of light at 350 nm, 1o emitted a strong blue fluorescence at 495 nm and the fluorescence intensity of 1o' (1o + Zn2+) had 58-fold increasement after adding Zn2+, the limit of detection (LOD) of 1o for Zn2+ was calculated to be only 14 nM. The 1:1 binding mode of 1o and Zn2+ was determined by Job's plot curves, NMR titration and mass spectrometry data. In addition, the 1o-Zn2+ complex could function as a reversible fluorescence photoswitch in the response to UV/vis light. Further, 1o was also successfully used to design a molecular logic gate, detect Zn2+ in real water samples and used as a test strip.

Automated summary

A new fluorescent chemosensor (1o) based on diarylethene was synthesized and showed highly selective recognition of Zn2+. The sensor exhibited good photochromic response under alternate irradiation of UV and visible light. It emitted strong blue fluorescence at a specific excitation wavelength, and the fluorescence intensity significantly increased after the addition of Zn2+, achieving a low limit of detection for Zn2+.