CA-5f is primarily used in research settings as a fluorescent probe for detecting and imaging reactive oxygen species, particularly hydroxyl radicals, in biological systems. Its high selectivity and sensitivity make it suitable for monitoring oxidative stress in live cells and tissues. It has been applied in studies related to neurodegenerative diseases, inflammation, and cancer, where oxidative damage plays a key role. Due to its cell permeability and low cytotoxicity, CA-5f enables real-time tracking of radical generation without significantly interfering with normal cellular functions. It is also used in high-throughput screening assays to evaluate the efficacy of antioxidant compounds.