Used as a pH indicator in analytical chemistry, particularly in titrations and biological experiments. It changes color from yellow to blue over the pH range of 3.8 to 5.4, making it suitable for detecting weak acids and bases. Commonly employed in enzyme assays and microbiological media to monitor pH changes during microbial growth. Also utilized in protein quantification methods, such as the determination of serum albumin in clinical diagnostics, where it binds selectively to albumin and produces a measurable color change. Its clear visual transition makes it valuable in educational labs for teaching acid-base chemistry.