Sulfonazo III salt is widely used as a sensitive and selective reagent in analytical chemistry, particularly for the determination of metal ions. It is commonly employed in spectrophotometric methods to detect and quantify trace amounts of metals such as calcium, magnesium, and rare earth elements in various samples, including water, soil, and biological fluids. The compound forms highly colored complexes with these metal ions, enabling precise measurements through UV-Vis spectroscopy. Additionally, Sulfonazo III salt is utilized in research and industrial applications for monitoring metal ion concentrations in environmental and biochemical studies, ensuring accurate analysis and quality control. Its stability and reactivity make it a valuable tool in complexometric titrations and metal ion chelation studies.