Highly selective ratiometric fluorescent Zn²⁺ chemosensor based on diarylethene derivative with...

An asymmetrical diarylethene (1O) with a bi-8-carboxamidoquinoline unit was synthesized. Its photochromic and fluorescence performances on stimulation with both light and metal ions showed that the diarylethene could serve as a highly selective ratiometric fluorescent chemosensor to detect Zn²⁺ ions based on internal charge transfer and chelation-enhanced fluorescence processes. The diarylethene could selectively discriminate Zn²⁺ from Cd²⁺ in acetonitrile. Furthermore, Job's plots based on fluorescence titration and electrospray ionization mass spectrometry analysis showed 1 : 1 binding stoichiometry between 1O and Zn²⁺ . The binding constant of 1O with Zn²⁺ , estimated using the Benesi-Hildebrand method, and the limit of detection were 3.37 × 10⁵  M^-1 and 4.6 × 10^-8 mol/L, respectively. Additionally, the light and metal-responsive fluorescence behavior of 1O was used successfully to construct a molecular logic circuit with four inputs and one output. Copyright © 2016 John Wiley & Sons, Ltd.