In article <04c6bcff.426ef119 at usw-ex0110-076.remarq.com>, Thomas <thomas.korosecNOthSPAM at univie.ac.at.invalid> wrote:
>The effect you are both observing, must have something to do
>with the type of membrane used. Using nitrocellulose
>membranes you will always get a perfectly red membrane, when
>you use Ponceau S AFTER blocking with low fat milk powder in
>TBS or BSA or whatsoever and after a "full" Western blot, of
>course.
>
And on the background of this "perfectly red membrane" (I'd describe
it as lightly pink after couple of water washes), there are _much_
more intense, red and perfectly clear bands of transferred proteins.
The sensitivity of Ponceau stain even _after_ the western is done
(_hours_ in 30 mg/ml milk/BSA) is about 0.2 ug BSA per band in
15 well minigel.
Looks like the kind of binding we get during transfer is not the same
as the one that occurs during blocking.
- Dima