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My protein samples are running abnormally on a SDS PAGE - (Nov/07/2011 )

Hi everyone,
I have a peculiar problem in sample running on a SDS PAGE. We use biorad 's mini protean gel apparatus for casting and running the gel. The running was really abnormal for the last two or three gels, the samples in the wells had a "V" shape as it was running, bulging of samples was also seen. I never had such a problem. Please see the images and give your comments. After running the gel I have proceeded further to western blotting which was also a failure.

P.S: Zoom out the second image for clarity.
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most of your samples are overloaded.


While I agree with mdfenko that you may have overloaded your samples, your stacking gel should have compacted these bands a lot more. Unless you aren't using a stacking gel.... Which leads to the question, what type of gel are you using? Are you rinsing out the wells with buffer before you load your samples? Is there more salt or additives in these samples than you have used previously?

All of these details are important when troubleshooting SDS-PAGE. If you can provide more information, we may be able to give you a more specific answer.

Best of Luck.


what is the source of the protein, is it a crude cell lysate or a purification of some sort... often a crude lysis will have a similar appearance to this, i also agree it is over loaded...