Used primarily as a fluorescent dye in biochemical and cellular studies to detect and measure reactive oxygen species (ROS). It is particularly valuable in assays that monitor oxidative stress in cells, as it becomes highly fluorescent upon oxidation. Additionally, it serves as a pH indicator in certain analytical applications, changing fluorescence intensity based on the acidity or alkalinity of the environment. Its sensitivity makes it a useful tool in microscopy and flow cytometry for visualizing cellular processes and assessing cell viability.