Sosnick:Rapid Coomassie Staining

Materials

Isopropanol fixing solution (see recipe)

Rapid Coomassie blue staining solution (see recipe)

10% (v/v) acetic acid

1. Place a polyacrylamide gel in a plastic or glass container. Cover the gel with 3 to 5 gel volumes isopropanol fixing solution and shake gently at room temperature. For a 0.7-mm-thick gel, shake 10 to 15 min; for a 1.5-mm-thick gel, shake 30 to 60 min.

2. Pour out fixing solution. Cover the gel with rapid Coomassie blue staining solution and shake gently until desired intensity is reached, 2 hr to overnight at room temperature. Bands will become visible even in the staining solution within 5 to 30 min, depending on gel thickness. The gel background will never stain very darkly.

3. Pour out staining solution. Cover the gel with 10% acetic acid to destain, shaking gently ≥2 hr at room temperature until a clear background is obtained.

4. If necessary, pour out 10% acetic acid and add more. Continue destaining until clear background is obtained.

Isopropanol fixing solution

25% (v/v) isopropanol

10% (v/v) acetic acid

65% H2O

Coomassie staining solution

10% (v/v) acetic acid

0.006% (w/v) Coomassie brilliant blue G-250

90% H2O

Adapted from ''Current Protocols in Molecular Biology ''