A conformation-dependent bifunctional fluorescent sensor for viscosity–pH monitoring in oxidative stress models

A conformation-dependent bifunctional sensor is developed by capitalizing on a vibration-induced emission chromophore for viscosity sensing and an acid-triggered oxazolidine switch for pH sensing. This design yields a large Stokes shift (>150 nm), enabling dual-channel and crosstalk-free monitoring of viscosity and pH in oxidative stress models.