Product Overview

1-Amino-2-naphthol-4-sulfonic Acid 95% AR (CAS No. 116-63-2) is a sulfonated aminonaphthol containing amino, phenolic hydroxyl, and sulfonic acid functionalities within a conjugated naphthalene structure. The amino and hydroxyl groups support electron-transfer reactions, while the sulfonic acid functionality facilitates its incorporation into aqueous analytical reagent systems. This combination gives the compound particular importance as a reducing reagent in colour-forming reactions involving heteropoly-molybdate species.

The AR grade is intended for analytical reagent preparation, quality-control work, method development, and research procedures requiring controlled reagent composition. It is especially suited to colorimetric determinations in which reduction of phosphomolybdate or silicomolybdate species produces an intensity of colour related to the concentration of the target analyte.

Typical Applications

• Reducing reagent in molybdenum-blue colorimetric procedures
• Colorimetric determination of phosphate in suitable aqueous samples
• Colour development in analytical methods for dissolved silica
• Preparation of aminonaphtholsulfonic acid reducing-reagent solutions
• Investigation of phosphomolybdate and silicomolybdate reduction reactions
• Development and verification of spectrophotometric methods involving heteropoly acids
• Routine analytical and quality-control procedures involving phosphorus or silicon species
• Research in inorganic colorimetry and analytical reaction chemistry

Common Synonyms

• 1-Amino-2-naphthol-4-sulphonic Acid
• 1,2,4-Aminonaphtholsulfonic Acid
• 1,2,4-Acid
• Aminonaphtholsulfonic Acid
• 4-Amino-3-hydroxynaphthalene-1-sulfonic Acid
• 1-Amino-4-sulfo-2-naphthol
• 2-Hydroxy-4-sulfo-1-naphthylamine
• ANSA

Storage Conditions

Store in a tightly closed container in a cool, dry, and well-ventilated location. Protect the material from direct light, moisture, contamination, and prolonged exposure to air. Keep it separated from strong oxidising agents, minimise dust formation during dispensing, and reseal the container promptly after use to preserve analytical reagent quality.