Used as a redox indicator in analytical chemistry, particularly in titrations to determine the concentration of vitamin C (ascorbic acid) in various samples. It is also employed in biochemical research to study oxidation-reduction reactions. In microbiology, it serves as a dye to differentiate and identify certain bacterial species based on their metabolic activities. Additionally, it is utilized in water quality testing to assess the presence of reducing agents. Its ability to change color upon reduction makes it a valuable tool in various laboratory applications.