Used as a reagent in analytical chemistry for the detection and quantification of oxidizing agents, particularly in colorimetric assays. It serves as a substrate for peroxidase enzymes, producing a visible color change upon oxidation, which allows for the measurement of enzyme activity or hydrogen peroxide levels in biological and environmental samples. Commonly applied in diagnostic test kits, research assays, and monitoring oxidative stress in clinical laboratories. Its high sensitivity and clear endpoint make it suitable for both qualitative and quantitative analysis.