Staining NC

[LOGAND]

MJ wrote:

>(deletion)

>I have been looking for a procedure to stain nitrocellulose membranes
>after transferring proteins from the polyacrylimide gel.  I have managed 
>to find out that I can use Coomassie, Amido Black, or Ponceau S, but I am
>unable to determine the advantages to each method.  I don't necessarily
>care if the stain is reversible, and we are amplifying the protein of
>interest, so I don't think concentration should be a problem.

>Any insights?  Does anyone have a preferred stain?


Dear MJ

Amido black is more sensitive than Ponceau S, also Ponceau S is difficult 
to record photographically (also it's not permanent)- however fine for 
marking positions of Mol. Wgt. markers before immuno-detection. Ponceau S 
is the quickest - pour on, agitiate (the blot) for few mins., pour off, 
wash in water and voila! Amido black may distort the NC since the gel is 
destained in 90% methanol 2% acetic acid. 
India ink is most sensitive and cheap - I'd choose it over amido black.
Choosing between India ink and Ponceau S depends on the need for permanence 
and sensitivity. 
I'd forget Coomassie as it distorts the membrane and can give high 
background.

Hope this helps.

David C. Logan
INRA-ENSA(M)-CNRS
Montpellier
FRANCE
Logand at msdos.inra.montpellier.fr