Naphthalene anhydride triphenylamine as a viscosity-sensitive molecular rotor for liquid safety inspection

Abstract

A viscosity-sensitive molecular rotor, DPPBQD, was successfully synthesized via a Suzuki coupling reaction. This molecular rotor—constructed from the naphthalene anhydride and triphenylamine moieties and formed into a typical twisted intramolecular charge transfer (TICT) system—was designed for the rapid detection of changes in viscosity during liquid spoilage processes. The rotor displayed high sensitivity, selectivity, photostability, universality and a large Stokes shift. Its fluorescence intensity was shown to be highly dependent on the extent to which the liquid food became corrupted. The developed strategy thus combines an analytical fluorescence technique with food safety inspection.