A near-infrared fluorescent probe for tracking endogenous and exogenous H2O2 in cells and zebrafish

H2O2 is an important signaling molecule in the body, and its levels fluctuate in many pathological sites, therefore, it can be used as a biomarker for early diagnosis of disease. Since the environment in vivo is extremely complex, it is of great significance to develop a probe that can accurately monitor the fluctuation of H2O2 level without interference from other physiological processes. Based on this, we designed and synthesized two new near-infrared H2O2 fluorescent probes, LTA and LTQ, based on the ICT mechanism. Both of them have good responses to H2O2, but LTA has a faster response speed. In addition, the probe LTA has good biocompatibility, good water solubility, and a large Stokes shift (95 nm). The detection limit is 4.525 μM. The probe was successfully used to visually detect H2O2 in living cells and zebrafish and was successfully used to monitor the changes in H2O2 levels in zebrafish due to APAP-induced liver injury.