
Alcian Yellow is a cationic (basic) dye primarily used in histological and microbiological staining. It belongs to the same family as Alcian dyes and is particularly valued for its ability to stain acidic mucopolysaccharides and microorganisms. It is often used in combination with staining techniques to enhance contrast and improve visualization of specific biological structures.
In histology, Alcian Yellow is most widely recognised as a component of the Alcian Yellow Toluidine Blue (AYTB) staining method, also known as the Leung stain.

CAS No.: 61968-76-1
Synonyms: Ingrain Yellow 1
| Physical Properties | |
| Chemical formula | C40H46N8S4 |
| Molecular weight | 767.11Â g/mol |
| Solubility | Soluble in Ethanol |
| Storage | Store At Room temperature |
| Chemical Properties | |
| Colour | Dark yellow |
| State | Solid |
| Melting point | 165-171° C |
| Odor | Characteristic |
| Pictograms : | Not Available  |
| Hazard Statements : | Not Available  |
| Precautionary statements : | Not Available  |
Alcian Yellow is a cationic (basic) dye primarily used in histological and microbiological staining. It belongs to the same family as Alcian dyes and is particularly valued for its ability to stain acidic mucopolysaccharides and microorganisms. It is often used in combination with staining techniques to enhance contrast and improve visualization of specific biological structures.
In histology, Alcian Yellow is most widely recognised as a component of the Alcian Yellow Toluidine Blue (AYTB) staining method, also known as the Leung stain.

CAS No.: 61968-76-1
Synonyms: Ingrain Yellow 1
| Physical Properties | |
| Chemical formula | C40H46N8S4 |
| Molecular weight | 767.11Â g/mol |
| Solubility | Soluble in Ethanol |
| Storage | Store At Room temperature |
| Chemical Properties | |
| Colour | Dark yellow |
| State | Solid |
| Melting point | 165-171° C |
| Odor | Characteristic |
| Pictograms : | Not Available  |
| Hazard Statements : | Not Available  |
| Precautionary statements : | Not Available  |
Alcian Yellow stains acidic mucopolysaccharides and mucins, highlighting structures rich in negatively charged polysaccharides.
Alcian Yellow and Alcian Blue are cationic (basic) dyes, but Alcian Blue is a copper phthalocyanine dye, while Alcian Yellow has a different heterocyclic structure (sulfur-containing, non-phthalocyanine). Alcian Yellow is used more selectively, often in combination staining methods (e.g., with toluidine blue for H. pylori), while Alcian Blue is mainly used for staining acidic mucopolysaccharides and mucins (especially in histopathology and GI studies).
Alcian Yellow binds to acidic mucins and negatively charged components in the gastric mucus through electrostatic interactions. It does not directly stain H. pylori strongly, but instead stains the surrounding mucus layer, creating a contrasting background that improves visualization. When used in combination with Toluidine Blue, the mucus appears highlighted by Alcian Yellow, while Helicobacter pylori organisms take up the Toluidine Blue counterstain and appear dark blue, making them easier to identify against the stained mucosal environment.
Alcian Yellow Toluidine Blue stain is a dual staining technique used primarily in histopathology for detecting Helicobacter pylori in gastric biopsy samples.