Thymol blue

Thymol Blue (thymolsulfonephthalein)

Dual-Range pH Indicator for Laboratory & Research Applications

Catalog Number: ASC-1036
CAS Number: 76-61-9
Molecular Formula: C₂₇H₃₀O₅S
Molecular Weight: 466.60 g/mol

Overview

Thymol Blue (thymolsulfonephthalein) is a synthetic sulfonephthalein dye widely used as a pH indicator in laboratory and research settings. It is supplied as a brownish-green to reddish-brown crystalline powder and is valued for its two well-defined colour transition ranges, allowing monitoring of both strongly acidic and moderately alkaline conditions.

Due to its clear and reproducible colour changes, Thymol Blue is commonly used in titrations, buffer preparation, analytical chemistry, and educational experiments where visual pH indication is required.

Ausamics Thymol Blue is supplied in high-purity laboratory grade, providing consistent colour response, solubility, and batch-to-batch reliability.

pH Transition Ranges

• Acidic range: Red → Yellow (approx. pH 1.2–2.8)

• Alkaline range: Yellow → Blue (approx. pH 8.0–9.6)

These dual transitions make Thymol Blue a versatile indicator for a wide range of laboratory applications.

Typical Applications

Analytical & Chemical Laboratories

• Acid–base titrations

• Buffer solution preparation and verification

• Monitoring pH changes in analytical procedures

Research & Teaching Laboratories

• Demonstration of pH-dependent colour indicators

• Educational experiments in chemistry and biochemistry

• Method development and optimisation

General Laboratory Use

• Visual pH monitoring in non-clinical research workflows

Key Features & Benefits

• Dual-range pH indicator in a single reagent

• Sharp, easily observable colour transitions

• Suitable for acidic and alkaline systems

• Reliable and reproducible performance

• Supplied with consistent quality and documentation

Physical & Chemical Properties

• Appearance: Brownish-green to reddish-brown crystalline powder

• Solubility: Soluble in alcohol; limited solubility in water

• Chemical Class: Sulfonephthalein dye

Storage & Stability

Store in a cool, dry place at 15–25 °C.
Protect from light and moisture.
Keep container tightly sealed when not in use.

Stable under recommended storage conditions.

Intended Use

For laboratory research and educational use only.

Not for human or animal use.
Not intended for diagnostic, therapeutic, veterinary, agricultural, food, or feed applications.

Quality & Documentation

• Certificate of Analysis (COA) available

• Safety Data Sheet (SDS) available upon request

• Manufactured and supplied under controlled quality conditions