A novel diarylethene-based fluorescent "turn-on" sensor for the selective detection of Mg.

A new photochromic diarylethene derivative with a 4-methylphenol unit has been designed and synthesized. It displayed distinct photochromism and fluorescent ''turn on'' features to Mg in acetonitrile solution. With the addition of Mg, there was an obvious increase of fluorescent emission intensity at 552 nm, accompanied by a clear change of fluorescent color from dark purple to green. Meantime, the 1 : 1 stoichiometry between the derivative and Mg was verified by Job's plot and HRMS. Furthermore, the sensor was successfully applied in the detection of Mg in practical samples. Moreover, based on the multiple-responsive fluorescence switching behaviors, it also could be used to construct a molecular logic circuit with UV/vis lights and Mg/EDTA as input signals and the emission at 552 nm as the output signal.