This staining takes a little longer than the normal “Hot Coomassie Staining”.
The advantages is:
a) More sensitivity
b) Also peptides are visible
c) Also lipophylic proteins stay in the gel during staining
d) Ideal for preparative 2D-stainings
The semi colloidal Coomassie-staining is staining and fixing at the same time.
The Phosphoric acid is less lipophilic than the Acetic acid.
This results in a slightly colloidal staining.
The 3% Acetic Acid is only used for getting the Coomassie better solubilized and we achieve therefor a „tank-clean“ staining recipe.
We recommend this method for peptides and preparative 2D-gels.
Stock solutions: (Volumes are given for normal sized gels, 12 × 26 cm)
staining solution: 0.01 % (w/v) Coomassie R 350 (GE: 1 tablet) in 2.8 L H2Odist
+ 0.5% (w/v) Phosphoric acid (18 mL) + 3% HAc (90 ml HAc) —> fill up to 3 L
destaining solutiont: 200 mL 10% HAc; 400 mL for large gels.
preserving solution: 200 mL 10% (v/v) glycerol; 400 mL for large gels