Turning on Light Emission of a Dark Pro-Aggregation-Induced Emission Luminogen in Aqueous Media Through Reductase-Modulated Derotation

Abstract

The development of dark pro-aggregation-induced-emission luminogens (pro-AIEgens) based on the solid-state intramolecular motion–caused quenching effect has been rarely reported in biochemical analysis. Herein, an azo-conjugated pro-AIEgen derived from tetraphenylethene is constructed. Due to the active molecular motion of the azo bond, it retains a nonemissive property in both solution and solid forms. The obtained pro-AIEgen can be internalized by living cells and undergo reductase-modulated derotation under hypoxia to emit light. It shows increasing fluorescence when the intracellular oxygen concentration becomes lower, making it a potential probe to sense the hypoxic environment. The present probe can also visualize the hypoxic environment created by photodynamic therapy treatment.