Test Catageory
فئة التحليل
Histopathology
Refrence Books
كتب مراجع
1. Bancroft’s Histopathological Techniques
Skills Required
المهارات المطلوبة
1. Histology
2. Staining
Video Resources
مصادر فيديو
Aim
To demonstrate all mucosubstances and differentiate between acid and neutral Mucin.
Principle
The section first stained with alcian blue which stain all acid mucins including that Are also PAS positive will not react with PAS. only neutral mucin will stain by PAS.
Solutions
Alcian blue………………………………….………………… stain acid mucin
2.1% periodic acid ………………………………………………oxidize 1-2 glycol
Bond to give aldehyde group
Schiff’s reagent……………………………………………. Stain neutral mucin
Sample Type
Formalin-fixed, paraffin-embedded (FFPE) tissue: This is a common type of sample used in histology, and it is suitable for the AB-PAS technique.
H&E slide: Hematoxylin and Eosin (H&E) stained slides can also be used for the AB-PAS technique.
Unstained slides: Unstained slides are also suitable for the AB-PAS technique
Procedure
1. Bring sections to distilled water.
2. Stain with Alcian blue 15 mins
3. Wash well in running tap water 2 mins
4. Rinse in distilled water
5. Treat with periodic acid 5 mins
6. Wash well in distilled water
7. Stain with Schiff’s reagent 10 mins
8. Wash well in R.T.W
9. Dehydrate, clear and mount
Results
Acidic mucins…………………………… Blue
Neutral mucins…………………………. Magenta
Mixtures of above ……………………. blue/purple
Notes:
1. Periodic acid is the oxidant of choice.
2. Other oxidants like potassium permanganate and chromic acid substitute Periodic acid
3. They tend to over oxidize the formaldehyde to carboxylic acid which result In a weak Schiff’s reaction.
4. Tap water after Schiff’s solution to intensify the colour of reaction.
M. Sulieman
mohammad@mlsgaate.com
1%Periodic acid will bring about oxidative cleavage of the Carbon-to-Carbon Bond in 1-2 glycol or their amino or alkyl-amino derivatives, to form Dialdehydes.
