ISilver Proteinate Staining-carbohydrate Staining for TEM

Staining indicates the presence of polysaccharides, glycoprotein or glycolipids containing vicinal hydroxyl groups

1. Collect sections on gold or nickel grids.

2. Float grids on drops of 1% Periodic Acid* for 30min at RT

3. Wash grids on drops of dH2O (3 x 10min)

4. Float grids on 0.2% TCH in 20% acetic acid** for 30min to 24hrs.

5. Wash grids in decreasing concentrations of acetic acid 20% -> 15% -> 10% -> 5% for 10 minutes each step. Then wash in dH2O (2 x15min)

6. Stain with 1% silver proteinate*** for 30min at RT in a dark, humid chamber.

7. Wash grids with dH2oO (2 x15min). Dry and observe on TEM. A fine electron deposit indicates positive staining.

*1% periodic acid is stable form 1 month at 4C. Corrosive

**0.2% TCH in 20% acetic acid is stable for several days at 4C

***1% silver proteinate should be prepared in advance (~12hr).   Sprinkle powder into water and leave to stand for 30minutes. Centrifuge prior to use. Light sensitive. Can be stored for 1 week at 4C