Product Overview

Alizarin Red S (CAS No. 130-22-3) is a water-soluble anthraquinone dye supplied as the monosodium salt of alizarinsulfonic acid. Its conjugated anthraquinone structure provides the chromophoric system responsible for its pronounced colour response, while the hydroxyl and sulfonate functionalities contribute to its interaction with ions in aqueous analytical systems. It is also identified by Colour Index number C.I. 58005.

The compound is distinguished by its ability to produce observable colour changes under different chemical conditions and to form coloured associations with calcium. These properties give Alizarin Red S particular value as a histological dye, mineralisation stain, and analytical indicator in laboratory procedures requiring visual or colorimetric detection.

Typical Applications

• Histological staining and localisation of calcium deposits
• Staining of bone, cartilage, and calcified biological structures
• Detection of extracellular calcium mineralisation in osteogenic cell cultures
• Qualitative and quantitative assessment of calcification in biological samples
• Whole-mount skeletal staining in anatomical and developmental studies
• Colorimetric evaluation of calcium-containing deposits
• Use as a pH indicator in analytical procedures
• Indicator and complex-forming dye in selected titrimetric and metal-ion studies

Alizarin Red S is widely established for calcium-related staining in histology and cell-culture mineralisation studies and is also supplied for analytical and indicator applications.

Common Synonyms

• Sodium Alizarinesulfonate
• Alizarin Red S Sodium Salt
• Alizarin Sodium Monosulfonate
• Alizarin Sulfonate Sodium
• Alizarinsulfonic Acid Sodium Salt
• Alizarin Carmine
• Mordant Red 3
• C.I. 58005
• 3,4-Dihydroxy-9,10-dioxo-2-anthracenesulfonic Acid Sodium Salt

Storage Conditions

Store in a tightly closed container in a cool, dry, and well-ventilated place. Protect the product from moisture, contamination, and strong oxidising agents. Reseal the container promptly after dispensing and handle the powder carefully to minimise dust formation.