Time-resolved dual-channel fluorescent probe for the detection of hypochlorite and sulfites during ferroptosis

Ferroptosis is an iron-dependent, non-apoptotic form of programmed cell death closely associated with various diseases. It is characterized by intracellular lipid peroxidation (LPO) and glutathione depletion. The process of lipid peroxidation is regulated by reactive oxygen species (ROS) and reactive sulfur species (RSS). Detecting ROS and RSS species during ferroptosis is particularly crucial for related research. However, the continuous temporal monitoring of these substances during ferroptosis remains an area that has not received sufficient attention. In this study, we constructed fluorescent probes ISE and ISEO to detect HClO and HSO₃^- during ferroptosis. Probe ISE enables dual-channel detection of HClO and HSO₃^- in yellow and blue channels, respectively. Probe ISE exhibits response times of 3 s for HClO and 45 s for HSO₃^-, with detection limits of 23 nM and 7 nM, respectively. Probe ISEO detects HSO₃^- through a change in the yellow-to-blue ratio. Probe ISEO has a response time of 80 s for HSO₃^-, with a detection limit of 26 nM. Both the probe ISE and ISEO demonstrate excellent imaging performance for detecting exogenous and endogenous targets within cells. Furthermore, the robust performance of the probes ISE and ISEO during ferroptosis in cells and zebrafish makes them extremely valuable for ferroptosis research.