Used as a fluorescent probe for detecting nitric oxide in biological systems. The compound easily penetrates cell membranes, where intracellular esterases remove the acetate groups, trapping the dye inside the cell. Once deacetylated, it reacts selectively with nitric oxide to form a highly fluorescent triazole product, allowing real-time visualization and quantification of nitric oxide production in live cells. Commonly applied in studies of cellular signaling, immune responses, and neuronal activity. Its high sensitivity and selectivity make it suitable for fluorescence microscopy and flow cytometry.