Quinoline-based fluorescent probe for ratiometric detection of hydrogen peroxide in aqueous solution

A novel quinoline-based fluorescent probe for detecting H2O2 is described. In aqueous solution, the probe exhibits fluorescence emission at 542 nm originating from the monocationic species. The reaction between the probe and H2O2 causes quenching of the emission at 542 nm and simultaneously yields a significant hypsochromic shift of the emission maximum to 480 nm due to the H2O2-triggered boronate cleavage process. Thus, a single-excitation, dual-emission ratiometric measurement with a large blue shift in emission (Δλ = 62 nm) and remarkable changes in the ratio (F480 nm/F542 nm) of the emission intensity (R/R0 up to 8.3-fold) can be established. Moreover, the probe can also afford high selectivity for detecting H2O2 over other biological reactive oxygen species.

► A new fluorescent probe for H2O2 is based on boronate deprotection mechanism.
► The probe can detect H2O2 through turn-on and ratiometric fluorescence signal output.
► This probe can avoid the influence from other reactive oxygen species and pH changes.