Ponceau S (C.I. 27195)

Ponceau S is used for reversible staining proteins blotted on nitrocellulose membran and while running a TAU electrophoresis. The reversibility of the staining process is ideally suited for subsequent immunoblots (western blot) or other colour reactions as Ponceau S can be completely removed. Ponceau S is not stable for long time, thus proteins and protein markers should be marked with a pencil. For staining the membrane is incubated in a 0.1% Ponceau S solution (w/v) in 5% acetic acid for 5 - 10 minutes. Destaining is done by incubating the stained membrane in 5% acetic acid for 15 minutes.