Used as a pH indicator in analytical chemistry, particularly in titrations involving weak acids and strong bases. It changes color in the pH range of 4.0 to 6.0, shifting from red (acidic) to blue (basic), making it useful for detecting the endpoint in certain acid-base reactions. Commonly applied in microbiology for staining procedures and in histology to differentiate tissue components under the microscope. Also employed in educational labs for demonstrating pH changes due to its clear and distinct color transition.