Re: P2D - questions

Mustafa Unlu (gen280@abdn.ac.uk)
Tue, 16 Feb 1999 01:31:51 +0000

Michael Johns wrote:
>
> Hi all,
>
> I have a few of questions concerning 2D SDS PAGE gel electrophoresis (using IPG strips):
>
> What would cause a spot to streak vertically from its origin towards the buffer front?

Some say that the excess DTT and dust cause the streaking and add a
second euilibration with 2% iodoacetamide in the equilibration step. Or
it could be the incomplete reformation of the S-S bonds after reduction,
which the IAA also takes care of.

> I seem to get blank areas after silver staining my 2D gels - any ideas to a cause? I use a silver diamine stain with 0.83% sodium thiosulphate in the gel matrix.

That is usually caused by having too much protein in that spot.


> What could cause a background 'cloud' near the end of a gel? I have tried reducing the IPG buffer down to 0.5% but still get a smear.

My guess is that it's crap in your sample buffer and/or bromophenol
blue.


> I have read quite a few troubleshooting guides and have not been able to solve the above questions. I am contemplating taking a 2D course. However, the only two I have found are in Europe. Does anyone know of a 2D electrophoresis course in North America?

Sorry can't help you there.


-- 
Regards,
Mustafa Unlu
University of Aberdeen
Proteomics Facility