This has been discussed here many time in the past. You can search this
newsgroup's archive at e.g. http://groups.google.com. Most probably you
have too much salt in your sample and should dialyze your sample prior to
boiling. Check for example this document (p.11)
http://www.gradigels.com/support/protocols/iGels%20Product%20Insert.pdf .
Reducing the sample volume might also help a bit.
Emir
"Katrin Westphal" <k.westphal at uni-bonn.de> wrote in message
news:3D73541D.F664307E at uni-bonn.de...
> Hi,
> I have problems with my SDS-PAGE: The bands grow wider the further they
> have run and the resolution grows bad: bands at the the top seem to be
> ok, while those at the bottom are blurred and much bigger than the ones
> above.
> My samples are bacterial membrane proteins or whole cell extracts in
> sodiumphosphate buffer.
>> Thanks in advance for any help!
>>>
