TAN is widely used as a spectrophotometric reagent for the detection and quantification of transition metals in various samples. It forms colored complexes with metals like copper, nickel, cobalt, and zinc, enabling their analysis through UV-Vis spectroscopy. This property makes it valuable in environmental monitoring for assessing metal contamination in water and soil. It is also employed in industrial quality control to ensure the purity of metal-based products. Additionally, TAN is utilized in research laboratories for studying metal ion interactions and developing analytical methods for trace metal analysis. Its sensitivity and selectivity make it a reliable tool in both qualitative and quantitative applications.