A pyrene-based ratiometric fluorescent probe with a large Stokes shift for selective detection of hydrogen peroxide in living cells.

Hydrogen peroxide (HO) plays a significant role in regulating a variety of biological processes. Dysregulation of HO can lead to various diseases. Although numerous fluorescent imaging probes for HO have been reported, the development of HO ratiometric fluorescent probe with large Stokes shift remains rather limited. Such probes have shown distinct advantages, such as minimized interference from environment and improved signal-to noise ratio. In this work, we reported a new pyrene-based compound as HO fluorescent probe in vitro. The probe demonstrated ratiometric detection behavior, large Stokes shift and large emission shift. In addition, the probe showed high sensitivity and selectivity towards HO in vitro. Based on these excellent properties, we successfully applied to the visualization of exogenous and endogenous HO in living cells. Cell imaging study also showed that our probe was localized in the mitochondria. We envision that the probe can provide a useful tool for unmasking the biological roles of mitochondrial HO in living systems.