A colorimetric and fluorescent chemosensor for Hg based on a photochromic diarylethene with a quinoline unit.

A new colorimetric and fluorescent 'on-off' chemosensor, 1O, based on a photochromic diarylethene with a quinoline unit was designed and synthesized. The chemosensor 1O demonstrated selective and sensitive detection of Hg ions in the presence of other competitive metal ions in acetonitrile. The stoichiometric ratio of the sensor 1O for Hg was determined to be 1 : 1, and the limit of detection of the probe 1O was calculated to be 56.3 nM for Hg. In addition, a molecular logic circuit with four inputs and one output was successfully constructed with UV/vis light and metal-responsive behavior. ESI-MS spectroscopy, Job's plot analysis, and H NMR titration experiments confirm the binding behavior between 1O and Hg.