Periodic Acid-Schiff Staining Protocol

Periodic-Acid Schiff (PAS) staining technique is used in histochemistry and histological studies to demonstrate the presence of carbohydrates and carbohydrate compounds such as polysaccharides, mucin, glycogen, and fungal cell wall components. It has been used to detect glycogen in tissues such as the skeletal muscles, the liver, the cardiac muscles. It uses formalin-fixed, paraffin-embedded tissue sections, or / and frozen tissue sections.

• Preparation of periodic acid solution. Mix 0.5 g periodic acid into 100 ml distilled water.
• Preparation of testing Schiff's reagent. 10 ml of 37% formalin, add Schiff's reagent to be tested.
• Preparation of Mayer's hematoxylin solution.
• Deparaffinize and hydrate water.
• Oxidation. Add 0.5% of the Periodic acid solution for oxidation for 5 minutes.
• Rinsing in distilled water.
• Alde hydration. Place the stain in Schiff reagent for 15 minutes, which turns light pink.
• Washing. Using lukewarm tap water, wash the stain for 5 minutes, turning it dark pink.
• Counterstaining. Add Mayer's Hematoxylin for 1 minute.
• Wash with running tap water for 5 minutes.
• Dehydrate and mount with a synthetic mount medium.

• A good Schiff reagent turns red-purple in color while a poor Schiff reagent will have a delayed reaction producing deep blue-purple coloration.
• Glycogen, mucin, elastic fibers, basophilic granules of the pituitary gland, reticular fibers, thyroid colloids, basement membranes, bone cartilage, and other carbohydrate components stain pink or purple.

Special Staining Services

Immunohistochemistry (IHC), Immunofluorescence (IF) Service

Transmission Electron Microscopy (TEM) Service