A fluorescent probe for detecting H₂O₂ and delivering H₂S in lysosomes and its application in maintaining the redox...

Hydrogen peroxide (H₂O₂) is a reactive oxygen species (ROS) that can be used as a marker for the occurrence of oxidative stress in the organism. Lysosomes serve as intracellular digestive sites, and when the concentration of H₂O₂ in them is abnormal, lysosomal function is often impaired, leading to the development of diseases. Hydrogen sulfide (H₂S) acts as a gaseous signaling molecule that scavenges H₂O₂ from cells and tissues, thereby maintaining the redox environment of the body. However, most of the reported hydrogen peroxide fluorescent probes so far can only detect H₂O₂, but cannot maintain the intracellular redox environment. In this paper, an H₂O₂ fluorescent probe LN-HOD with lysosomal targeting properties was designed and synthesized by combining the H₂O₂ recognition site with a naphthylamine fluorophore via a thiocarbamate moiety. The probe has the advantages of large Stokes shift (110 nm), high sensitivity and good H₂S release capability. The probe LN-HOD can be used to detect H₂O₂ in cells, zebrafish and plant roots. In addition, LN-HOD detects changes in the concentration of H₂O₂ in plant roots when Arabidopsis is stressed by cadmium ion (Cd²⁺). And through its ability to release H₂S, it can help to remove excess H₂O₂ and maintain the redox environment in cells, zebrafish and plant roots. The present work provides new ideas for the detection and assisted removal of H₂O₂, which contributes to the in-depth study of the cellular microenvironment in organisms.