Description

Methyl Red Sodium Salt CAS NO 845-10-3 is the water-soluble sodium salt form of the common pH indicator Methyl Red. This compound matters for its precise and reliable color transition in the critical pH range of 4.4 to 6.2, making it an indispensable tool for analytical and microbiological procedures. Industries and laboratories that require accurate pH determination, such as pharmaceutical manufacturing, academic research, and quality control in chemical production, depend on its consistent performance.

Application

• Microbiological Media: A key component in diagnostic media like Methyl Red-Voges Proskauer (MR-VP) broth for the identification of enteric bacteria, including E. coli.
• pH Indicator Solutions: Used to prepare precise aqueous pH indicator solutions for titrations and endpoint detection in analytical chemistry.
• Laboratory Reagent: Employed as a standard reagent in educational, research, and industrial laboratories for acid-base experiments and demonstrations.
• Quality Control Testing: Utilized in various industrial QC protocols to monitor pH changes during chemical synthesis and fermentation processes.
• Histological Staining: Acts as a counterstain or pH indicator in certain specialized histological and cytological staining techniques.

Basic Information

Product Name	Methyl Red Sodium Salt
CAS No.	845-10-3
Molecular Formula	C15H14N3NaO2
Molecular Weight	291.28 g/mol
Synonyms	Acid Red 2 Sodium Salt; Sodium Methyl Red; 2-[4-(Dimethylamino)phenylazo]benzoic Acid Sodium Salt; C.I. 13020; Methyl Red, Sodium Salt; MR Sodium Salt; Benzoic acid, 2-[4-(dimethylamino)phenyl]azo]-, sodium salt; Gold Indicator (in specific contexts)
EINECS	212-682-9

Quality Control

Our Methyl Red Sodium Salt is manufactured under a rigorous quality management system. Each batch is tested to ensure it meets stringent specifications for identity, purity, and performance as a pH indicator. A comprehensive Certificate of Analysis (COA) detailing assay, loss on drying, absorbance characteristics, and other critical parameters is provided with every shipment to guarantee traceability and compliance.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at room temperature (15-25°C). The product is light-sensitive (store away from light). Keep the container tightly sealed to protect from moisture.

Specification

Item	Specification
Appearance	Dark red to reddish-brown powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Loss on Drying	≤ 5.0 %
pH Transition Range	4.4 (Red) - 6.2 (Yellow)
Absorbance (in buffer)	Conforms
Solubility (Water)	Freely soluble

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