Description

Chromotropic Acid Sodium Salt is the sodium salt derivative of chromotropic acid, a key organic compound used as a sensitive and selective reagent in analytical chemistry. Its primary commercial value lies in its ability to form stable, colored complexes with specific analytes, enabling precise quantitative and qualitative analysis. This product is essential for manufacturers and laboratories in the chemical, pharmaceutical, and environmental sectors requiring reliable detection methods.

Application

• Formaldehyde Detection and Analysis: The most prominent application, used as a specific colorimetric reagent for the quantitative determination of formaldehyde in air, water, resins, and consumer products.
• Analytical Chemistry Reagent: Employed in the spectrophotometric analysis of various aldehydes, ketones, and other organic compounds that form chromogenic derivatives.
• Pharmaceutical Testing: Utilized in quality control laboratories for the assay and impurity profiling of drug substances and excipients that release formaldehyde or related compounds.
• Environmental Monitoring: Applied in test kits and standardized methods for monitoring formaldehyde levels in indoor air, industrial emissions, and wastewater.
• Textile and Resin Industry QC: Used to test for residual formaldehyde in textiles, leather, and urea-formaldehyde or phenol-formaldehyde resins.
• Research & Development: Serves as a fundamental reagent in synthetic chemistry and biochemical research for developing new analytical methodologies.

Basic Information

Product Name	Chromotropic Acid Sodium Salt
CAS No.	3888-44-6
Molecular Formula	C10H6Na2O8S2 • xH2O
Molecular Weight	Anhydrous: 364.22 g/mol
Synonyms	4,5-Dihydroxynaphthalene-2,7-disulfonic Acid Disodium Salt; Chromotropic Acid Disodium Salt; 1,8-Dihydroxynaphthalene-3,6-disulfonic Acid Disodium Salt; Sodium Chromotropate; Disodium 4,5-dihydroxy-2,7-naphthalenedisulfonate; C.I. 23635; Chromotrope 2B intermediate
EINECS	223-418-3

Quality Control

Our Chromotropic Acid Sodium Salt is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets high-purity standards suitable for sensitive analytical applications. A comprehensive Certificate of Analysis (COA) detailing purity, identity, and impurity profiles is provided with every shipment to guarantee traceability and consistency for your critical processes.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at a controlled room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed after each use to prevent absorption of atmospheric moisture, which can affect purity and performance.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Loss on Drying	≤ 2.0%
Water Content (KF)	Contact for details
Heavy Metals (as Pb)	≤ 20 ppm
Residue on Ignition	Contact for details
Solubility (in Water)	Clear, yellow solution

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