Description

Sodium Thymol Blue is a high-purity sodium salt of thymolsulfonphthalein, widely recognized as a versatile acid-base indicator and complexometric titration reagent. Its distinct color transition across a broad pH range makes it an indispensable tool for precise endpoint detection in analytical chemistry and quality control laboratories. This compound is essential for professionals in the pharmaceutical, chemical manufacturing, and water treatment industries who require reliable and consistent analytical results.

Application

• Acid-Base Titrations: Primary use as a visual pH indicator with transitions in both acidic and alkaline ranges.
• Complexometric Titrations: Employed as a metallochromic indicator for the titration of various metal ions, including calcium and magnesium.
• Laboratory Reagent: Used in the preparation of standardized test solutions and buffer solutions for analytical procedures.
• Educational Kits: A key component in chemistry educational sets for demonstrating titration principles and pH concepts.
• Water Hardness Testing: Applied in methods for determining the concentration of calcium and magnesium ions in water samples.
• Pharmaceutical Analysis: Utilized in QC labs for the assay of raw materials and finished products where precise titration is required.

Basic Information

Product Name	Sodium Thymol Blue
CAS No.	62625-21-2
Molecular Formula	C27H29NaO5S
Molecular Weight	488.57 g/mol
Synonyms	Thymol Blue, Sodium Salt; Thymolsulfonphthalein, Sodium Salt; 4,4'-(3H-2,1-Benzoxathiol-3-ylidene)bis(5-methyl-2-(1-methylethyl)phenol) S,S-Dioxide, Sodium Salt; Sodium Thymolsulfonphthalein; NSC 9245; Thymol Blue Indicator; Acid-base Indicator Thymol Blue; CI 19140
EINECS	263-583-8

Quality Control

Our Sodium Thymol Blue is manufactured under strict quality management systems to ensure batch-to-batch consistency and high performance. Each lot is tested to confirm identity, purity, and suitability for use as a precise analytical indicator. A comprehensive Certificate of Analysis (COA) detailing assay, loss on drying, and specific absorbance 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). Keep the container tightly sealed when not in use to prevent moisture absorption and contamination.

Specification

Item	Specification
Appearance	Dark green or brownish-green powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Loss on Drying	≤ 5.0 %
pH Transition Range	1.2 (red) - 2.8 (yellow); 8.0 (yellow) - 9.6 (blue)
Absorbance (Specific)	Conforms
Solubility	Soluble in water and ethanol

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