Semi-dry transfer buffer (Bjerrum Schafer-Nielsen) recipe
The transfer buffer for semi-dry blotters: 48 mM Tris, 39 mM glycine, 20% methanol, 0.0375% SDS.
🧮 Volume calculator
| Component | Amount | Final concentration (1X) |
|---|---|---|
| Tris base | 2.905 g | 48 mM |
| Glycine | 1.465 g | 39 mM |
| 10% SDS | 1.875 mL | 0.0375% |
| Methanol | 100 mL | 20% |
| Water (distilled) | to final volume |
Steps
- Dissolve Tris and glycine in water and add SDS (do not adjust pH; ≈9.2).
- Add methanol and bring to volume.
- Pre-chill at 4 °C before use.
Good to know
- Soak filter papers and membrane thoroughly and stack without bubbles.
- Large proteins (>150 kDa) transfer better by wet transfer.
⚠ Safety Methanol is toxic and flammable.
FAQ
Can I use Towbin wet-transfer buffer?
Many labs do. With the small buffer volume of semi-dry, this SDS-containing recipe transfers a wider size range more evenly.
This is a widely used standard composition. Amounts depend on the hydrate form and purity of your reagents — check the formula weight (FW) on the bottle and follow your institution's safety rules and the manufacturers' instructions.