A new diarylethene based chemosensor for colorimetric recognition of arginine and fluorescent detection of Cu2+

A novel diarylethene derivative with a benzothiazolinone hydrazone unit was synthesized as a new chemical sensor, the photochemical properties and ion selectivity were studied. It not only acted as a colorimetric sensor for detecting arginine in the ring-closed isomer, but also served as a fluorescence sensor for detecting Cu2+ in the ring-open isomer. When various metal ions were added to the sensor solution respectively, only Cu2+ resulted in an obvious quenching of fluorescence, and the fluorescence color changes from yellow to black. What's more, upon the addition of arginine, the color of the ring-closed isomer's solution changed from purple to blue, which was attributed to the proton transfer from ring-closed isomer to arginine, it can be proved by H-1 NMR spectrum. Furthermore, the chemosensor could also be made into test papers for detecting Cu2+ in actual water samples.