Description

4-(2,4-Dihydroxyphenylazo)-3-Hydroxy-1-Naphthalenesulfonic Acid Sodium Salt is a high-purity azo dye intermediate and analytical reagent. This compound is valued for its strong chelating properties and chromogenic reaction with specific metal ions, making it a critical component in specialized chemical synthesis and testing protocols. It is primarily sought by manufacturers and research laboratories in the analytical chemistry, dye and pigment production, and metallurgy sectors for its precise performance characteristics.

Application

• Analytical Reagent: Used as a sensitive colorimetric indicator and complexometric titrant for the detection and quantification of metal ions such as aluminum, magnesium, and calcium.
• Dye Intermediate: Serves as a key precursor in the synthesis of specific azo dyes and pigments, particularly those requiring light-fastness and metal-complex structures.
• Biochemical Staining: Employed in histological and cytological staining procedures in life science research.
• Chelating Agent: Functions as a selective chelator in chemical processes and water treatment formulations to sequester specific metal cations.
• Photometric Analysis: Utilized in the development of photometric test kits and sensors for environmental and industrial monitoring.
• Research & Development: A valuable tool in academic and industrial R&D for studying coordination chemistry and developing new chromogenic assays.

Basic Information

Product Name	4-(2,4-Dihydroxyphenylazo)-3-Hydroxy-1-Naphthalenesulfonic Acid Sodium Salt
CAS No.	6409-02-5
Molecular Formula	C16H11N2NaO6S
Molecular Weight	382.32 g/mol
Synonyms	Aluminon; Aurintricarboxylic Acid Ammonium Salt (related); 5-[(3-Carboxy-4-hydroxyphenyl)(3-carboxy-4-oxo-2,5-cyclohexadien-1-ylidene)methyl]-2-hydroxybenzoic Acid Triammonium Salt (related); C.I. 43810; Acid Chrome Blue K; Aluminum Indicator; Ammonium Aurintricarboxylate; 3-Hydroxy-4-(2,4-dihydroxyphenylazo)-1-naphthalenesulfonic Acid Sodium Salt
EINECS	229-068-1

Quality Control

Our production of 4-(2,4-Dihydroxyphenylazo)-3-Hydroxy-1-Naphthalenesulfonic Acid Sodium Salt adheres to stringent in-process controls to ensure batch-to-batch consistency and high purity. Every lot is analyzed against established specifications for identity, assay, and impurity profiles. A Certificate of Analysis (COA) detailing all relevant quality parameters is provided with each shipment to support your quality assurance protocols.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). This product is hygroscopic (moisture-sensitive); ensure the container is kept tightly sealed to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	Orange to reddish-brown powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Loss on Drying	≤ 5.0%
Residue on Ignition (Sulfated Ash)	≤ 1.0%
Heavy Metals (as Pb)	≤ 20 ppm
Solubility (in Water)	Clear, orange-red solution

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.