New recipe: we replaced the methanol with ethanol! 2. Staining with Coomassie Blue G-250 (EtOH) Stock solutions:
TCA: 20% TCA: Dilute 40 ml of 100 % TCA (1kg/l) to 200 ml A: 0.2% CuSO4 / 20% acetic acid: Dissolve 2 g of CuSO4 x 5 H2O in 1 l of 20% (v/v) acetic acid. B: 0.04% Coomassie G-250 in 25% (v/v) ethanol: 0.4g Coomassie G-250 + 250 ml Ethanol + 750 ml H2O C: 20% (v/v) Ethanol: 200 ml Ethanol + 800 ml H2O
Staining programme:
Fix: 20 min in 200 ml 20% (w/v) TCA Rinse 5 min 200 ml H20 Bidest Wash: 5 min in 200 ml wash solution (mix equal amounts of A and C) Stain: 30 min in 200 ml of staining solution (mix equal amounts of A and B) (pre-heat the staining solution to 50°C while stirring). See the picture below! Destain: 2-3 x 20 min* in wash solution (in a tray), best is 1 x overnight Impregnate: 5 min in 200 ml 5 % (v/v) glycerol Dry: leave at room temperature, overnight * = visual control
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