Problem with SDS PAGE - (Jan/12/2009 )

Hi everyone,
i am having a 10kD peptide, and i run SDS PAGE for couples time with 10%, 17%(twice), but i still can not see anything at around 10kD.
Could someone help me out....

Thanks
Danny

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Are you fixing your gel in glutaraldehyde after electrophoresis?
Do you use low or ultra-low MW marker? Is it visible?

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I didnt fix my gel at all, do i have to ?
my marker lowest limit is 12kDa

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10 kDa is very small, maybe you should try to use gradient gels or tris-tricine system, this is more suitable for proteins of that size and will give you better results.

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Thanks biomaus

btw, do you know anything about fixing the peptide at the end of gel ?
since i went through some of the posts here.. and they all said that fixation peptide.
when do i have to fix the peptide? depend on the size of the peptide? or what?

thanks again

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Most simple way to fix your gel is to put it in 5% glutaraldehyde solution (in water) for 30-60 minutes, then wash it 3x for 5-15 min in water.

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Is it a must for fixing the gel ?

Thanks

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unless you are going to elute or transfer the gel, yes.

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would it be possible that the peptide escape from the gel during the staining process?
Since i read some articles, and saying that it would actually happen.

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