Acetylation
For the Periodic Acid-Schiff Reaction
This procedure is used in the Periodic Acid-Schiff (PAS) reaction to block hydroxyl and amino groups. It does this by forming esters with them. As a consequence some carbohydrates fail to react with the Schiff’s reagent. This may be used as a means of identifying them, particularly if done in conjunction with other blocking procedures.
Materials
| Material | Amount | |
|---|---|---|
| Acetic anhydride | 16 | mL |
| Pyridine, anhydrous | 24 | mL |
Procedure
Place dewaxed sections into the solution at the temperature specified for the time given.
| Tissue | Temperature | Time | State |
|---|---|---|---|
| Cartilage | 58°C | 6 hours | Complete |
| Cartilage | 25°C | 24 hours | Complete |
| Glycogen | 25°C | 6 hours | Almost complete |
| Epithelial mucin | 25°C | 6 hours | Complete |
Safety Note
Prior to handling any chemical, consult the Safety Data Sheet (SDS) for proper handling and safety precautions.
References
- Lillie, R.D., (1954)
Histopathologic technique and practical histochemistry Ed.2
Blakiston, New York, USA.
