Hi, i have a problem in SDS-PAGE. i used a very hrdrophobic peptide to run 20% SDS PAGE. In the normal concentration of SDS (0.1%) in gel, i can't find any interaction of the peptide. But once i found when the conc. of SDS increase to 1% in gel. i found the dimer band and tetramer. In the analysis, the conc. of SDS in the sample buffer must lower than 1% to see the dimer band. i don't know how to explain this result! Can someone help me? Thanks!

Thats a tough one. Based off logic and no sound data, I can only think that the pH or salt concentration in the gell affects the stability of the peptide/protein interaction. I'll do some looking and get bak to you. Also check out this post in this category on the priniciple of SDS-gels for clues.

http://www.scientistsolutions.com/t3515-SDS_PAGE+%26quot%3BHall+of+Shame%26quot%3B.html


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