IP lysis buffer (for Co-IP) recipe
A gentle buffer that lyses cells while preserving interactions for IP and Co-IP: 25 mM Tris pH 7.4, 150 mM NaCl, 1 mM EDTA, 1% NP-40, 5% glycerol.
🧮 Volume calculator
| Component | Amount | Final concentration (1X) |
|---|---|---|
| 1 M Tris-HCl (pH 7.4) | 1.25 mL | 25 mM |
| 5 M NaCl | 1.5 mL | 150 mM |
| 0.5 M EDTA | 100 µL | 1 mM |
| NP-40 (or IGEPAL CA-630) | 500 µL | 1% |
| Glycerol | 2.5 mL | 5% |
| Water (distilled) | to final volume |
Steps
- Combine all stocks, NP-40 and glycerol with water.
- Bring to the final volume with water.
- Store at 4 °C.
- Add protease inhibitors (and phosphatase inhibitors if needed) just before use.
Good to know
- For weak interactions lower NaCl to 100 mM or NP-40 to 0.5%; raise them if background is high.
FAQ
Do I need a separate wash buffer?
Usually the same buffer (or with NP-40 lowered to 0.1%) is used for washes.
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.