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how to label all proteins after western-blot - someting like ponceau red, but after blocking (Jul/13/2006 )

Hello there,

I did a western-blot after biotinylated proteins capture. I still cannot see the band I'm interested in. I"m wondering if I managed to capture the proteins or not.

I have a question : is there a way to color all proteins on a nitrocellulose membrane, after western-blotting? (i.e. after blocking and incubating antibodies)

I guess that I will have troubles because of blocking with 3% BSA and milk 1%.
I tried once with coomassie blue, because a collegue of mine manage to color his PVDF membrane after western-blot, but my nitrocellulose membrane become simply completely blue.

May be I should strip and try ponceau red, or coomassie?

Thanks in advance



if you want stgh to stain proteins, you'll surely label milk proteins and BSA. so the whole membrane will be red. So i think that youl'' better have to strip the membrane and stain with ponceau red


QUOTE (Missele @ Jul 14 2006, 03:07 AM)
May be I should strip and try ponceau red, or coomassie?

i think this is the solution if u do stain ur whole membrane it will stain all the proteins in ur case( blocking\).


Thank you spanishflower and Fred,

i will strip, no miracle.
lucky guys the one who use PVDF, it works even if you block !
but nitrocellulose has other advantages wink.gif


woaw "la nuit porte conseil", it means night gives you good advie.
however I realize I only wake up at 10:00 am laugh.gif
it's biotinylated proteins. I will put some streptavidin-HRP and detect them ! laugh.gif
Sorry again for asking you such a stupid question.

(I really need holidays)


mais le matin est plus malin...
since you are able to adjust your exp, there is no problem. And there is no stupid question....


QUOTE (fred_33 @ Jul 19 2006, 06:37 PM)
mais le matin est plus malin...

I didn't know this one.

Thanks Fred.

Ok then , I think it's time to go home. I'll be more smart tomorrow morning !