Alcian Blue
Classification: Carbohydrate stain
Purpose: stain Group II & III Carbohydrates –Sulfated and carboxylated acid mucopolysaccharides – Sulfated and carboxylated sialomucins (glycoproteins)
Mechanism of staining: Ionic bonding or salt linkage
Control tissues: small intestine or large intestine
Alcian Blue (pH 2.5)
–Mucopolysaccharides and sialomucins - dark blue
Background - pink to red
Nuclear fast red counterstain
Demonstrates both sulphated and carboxylated acid mucopolysaccharides and sulphated and carboxylated sialomucins at pH 2.5.–
Small intestine
REAGENT |
PURPOSE |
MECHANISM OF STAINING |
SOURCE OF ERROR |
Alcian blue in 3% acetic acid For pH 2.5 |
Amphoteric dye Demonstrate carboxylated & sulphated mucopolysaccharides
and sialomucins (progressively and directly) |
Salt linkage - attaches to negatively charged acid
mucopolysaccharides and sialomucins to produced an insoluble end product |
Omitted: Omitted: target carbohydrates will
be not be demonstrated. |
Too short: Target will be lightly stained. |
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Too long: Background staining and darkly stained target
tissue. |
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Alcian blue in water For pH 1.0 |
Amphoteric dye Demonstrate sulphated only mucopolysaccharides and sialomucins (progressively and directly) |
Salt linkage - attaches to negatively charged acid
mucopolysaccharides and sialomucins to produced an insoluble end product |
Omitted: Target carbohydrates will be not be demonstrated. |
Too short: Target will be lightly stained. |
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Too long: Background staining and darkly stained target
tissue. |
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Nuclear fast red |
Counterstain |
|
Omitted: Other tissue components not
demonstrated. |
Too long: Other tissue components stain
darkly and obscure the primary stain. |
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Too short: Other tissue components stain
lightly or are not demonstrated. |
Alcian Blue (pH 1.0)
Periodic Acid Schiff and Hematoxylin counterstain
Sulphated mucopolysaccharides - pale blue
Background - pink to red
Demonstrates sulphated mucopolysaccharides and sialomucins at pH 1.0
Alcian Blue
Periodic Acid Schiff and Hematoxylin counterstain
Alcian Blue
Counterstain - Hematoxylin
Special Considerations
A variety of counterstains can be used including: Hematoxylin, Periodic Acid Schiff, Nuclear Fast Red, and Van Geison.
Alcian blue is a basic and amphoteric dye. Adjusting the pH of Alcian blue alters the type of tissue it can bond with. At pH 2.5, both sulphated and carboxylated acid mucopolysaccharides and sialomucins are demonstrated. At pH 1.0, only sulphated mucopolysaccharides and sialomucins are demonstrated.
References
Officer B. HIML251 Lecture notes: Alcian Blue and Masson Trichrome stains, January 28, 2009