Used as a chelating agent in analytical chemistry for the detection and determination of metal ions such as iron, copper, and silver. Forms stable colored complexes that are useful in spectrophotometric analysis. Commonly employed in redox titrations and as an indicator in oxidation-reduction reactions. Acts as a ligand in coordination chemistry to stabilize metal centers in catalytic reactions. Also applied in the synthesis of sensors and in biochemical assays for studying metal-dependent enzyme activity.