Methanol/Chloroform Protein Precipitation

Methanol/Chloroform Protein Precipitation

Note: This method can be scaled up or down.

1. To a sample aliquot of 100 uL starting volume add 400 uL Methanol.

2. Vortex well.

3. Add 100 uL Chloroform.

4. Vortex well.

5. Add 300 uL ddH20. Sample should look cloudy.

6. Vortex well.

7. Spin 2 to 5 minutes at 14,000 g.

8. Pipette off the top aqueous layer. Protein exists between layers and may be visible as a thin wafer.

9. Add 400 uL of Methanol.

10. Vortex well.

11. Spin 3 t 5 minutes at 14,000 g.

12. Pipette as much Methanol as possible from the tube without disturbing the pellet.

13. Speed-Vac to dryness but avoid drying too long as this makes the pellet harder to re-solubilize.