Fluorescent Detection of Dynamic H₂O₂/H₂S Redox Event in Living Cells and Organisms

The elusive mechanism of action between signaling molecules H₂O₂ and H₂S in oxidative stress demands a fluorescent probe, capable of their detection in a discriminative and dynamic manner. Herein we report the design and study of a probe TCAB. As demonstrated, it responds to H₂O₂ and H₂S selectively and sensitively to generate distinct fluorescence signals and patterns. Cyan imaging for H₂O₂ in a ratiometric fashion and two-colored, enhanced blue and newly produced red for H₂S are observed. When both are present, the sequential reaction of H₂O₂ and H₂S with the probe gives cyan then red signal, while the reverse sequence produces an inverse red-cyan signal. The unrivaled discriminative multicolor imaging capacity of the probe enables us to monitor dynamic H₂O₂ and H₂S redox processes in living cells and organisms. It is expected that the probe could serve as a powerful tool to investigate the correlation and distinction of biologically significant H₂S- and H₂O₂-engaged redox processes.