Description

Chromotrope 2R is a synthetic azo dye widely recognized for its use as a biological stain and pH indicator in analytical chemistry. Its consistent performance and high purity are critical for ensuring reliable and reproducible results in sensitive laboratory and industrial applications. This product is essential for professionals in histology, textile dyeing, and research laboratories requiring precise colorimetric analysis.

Application

• Histological Staining: Used as a cytoplasmic stain in biological sample preparation for microscopy.
• Textile Dyeing: Imparts color to protein-based fibers like wool and silk.
• pH Indicator: Serves as a colorimetric indicator in analytical chemistry procedures.
• Biological Research: Employed in various staining protocols for tissue and cell analysis.
• Ink Formulation: A component in the manufacture of specialized inks and colorants.
• Laboratory Reagent: Used as a standard or reagent in chemical analysis and quality control testing.

Basic Information

Product Name	Chromotrope 2R
CAS No.	4197-07-3
Molecular Formula	C16H10N2Na2O8S2
Molecular Weight	468.36 g/mol
Synonyms	Acid Red 29; Chromotrope 2R; C.I. 16570; Sodium 4-[(2,4-dinitrophenyl)azo]-1-naphthol-5,7-disulfonate; Chromotrope 2R disodium salt; Chromotrope 2R sodium salt; Mordant Black 17; Chromotrope FB
EINECS	224-077-1

Quality Control

Our Chromotrope 2R is manufactured under strict quality management systems to ensure batch-to-batch consistency and high purity. Each lot is tested against rigorous internal specifications, which include identity confirmation, assay, and impurity profiling. A Certificate of Analysis (COA) detailing all test results is provided with every 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 a controlled room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed when not in use to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	Reddish-brown to dark red powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Loss on Drying	≤ 5.0%
Water Solubility	Freely soluble
pH (1% Solution)	6.0 - 8.0
Heavy Metals (as Pb)	≤ 20 ppm

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