Product Overview

Alizarin Red S AR (CAS No. 130-22-3) is an analytical reagent grade, water-soluble anthraquinone dye supplied as the sodium salt of alizarinsulfonic acid. Its extended conjugated structure produces a distinct colour response, while its ionisable functional groups enable pH-dependent transitions and interactions with selected metal ions. These characteristics make Alizarin Red S useful as an analytical indicator and colour-forming reagent in laboratory chemistry.

The AR grade is intended for analytical, quality-control, research, and academic laboratories requiring consistent reagent quality and a dependable indicator response. It is suitable for visual endpoint detection, pH-indicator procedures, and analytical methods based on controlled colour development or metal–dye complex formation.

Typical Applications

• pH-indicator procedures and visual transition studies
• Endpoint indication in suitable titrimetric methods
• Preparation of analytical indicator and test solutions
• Colorimetric and spectrophotometric method development
• Analytical studies involving complex formation with selected metal ions
• Evaluation of pH-dependent colour behaviour
• Routine quality-control and analytical laboratory procedures
• Academic experiments in indicator, dye, and coordination chemistry

Alizarin Red S is commercially recognised as a reagent for analysis and indicator use, with established suitability for titrimetric procedures and analytical investigations involving metal-ion complexation.

Common Synonyms

• Alizarin Red S
• Sodium Alizarinesulfonate
• Alizarin Red S Sodium Salt
• Alizarin Sodium Monosulfonate
• Sodium Alizarin-3-sulfonate
• Alizarin Carmine
• Mordant Red 3
• C.I. 58005
• Alizarinsulfonic Acid Sodium Salt

Storage Conditions

Store in a tightly closed container in a dry and well-ventilated place at room temperature. Protect the product from moisture and contamination, and reseal the container promptly after dispensing to preserve reagent quality.