The alcian blue stain is this author’s preferred stain for the demonstration of acidic mucins. The dye was originally used for the dyeing of cotton before being discovered as a by Steedman in 1950.
The alcian blue itself is a cationic copper phthalocyanine dye which stains mucopolysaccharides and glycosaminoglycans a bluish colour. Within skin, acidic mucins can be found in many differing conditions such as a mucinoma, lupus and alopecia mucinosa.
Below is the preferred alcian blue method of this author
1g alcian blue in 3% acetic acid (check pH = 2.5)
1. Take sections to water
2. Cover slide with FILTERED alcian blue solution and leave for 20 minutes
3. Rinse in tap water
4. Counterstain with FILTERED 1% safranin for 10-15 seconds
5. Rinse in tap water
6. Dehydrate quickly, clear and mount.
– this author prefers an alcian blue staining time of about 20 minutes but can be done within the range of 10-30 minutes if desired.
– by reducing the pH to 0.2 the stainer can select for only strongly sulphated mucins. A pH of 1.0 stains both weak and strongly sulphated mucins. If using a lower pH method be sure no to rinse in tap water between the steps for too long as this can affect the alcian blue staining.
– this author prefers safranin as a counterstain due to its crisper staining, but safranin leeches out quickly in the dehydrating alcohols therefore blot dry after counterstaining and quickly dehydrate through the alcohols.
– neutral red can also be used as a counterstain.
– the alcian blue staining solution expires after approximately 6 months.
Thanks for reading and I welcome any comments and other tips.
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