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Acrylamide stock - (Dec/10/2010 )

pito on Sat Apr 25 15:48:41 2009 said:

Anyone who reads this topic or needs info on the subject, be sure check the files attached.

Hi everybody,

In SDS-PAGE, my separating solution is not fully gelled. Everytime i get 200 to 500ul of extra solution without gelled. i would like to know what is reason for this and how to correct it.


How do you mean? You make up a working solution, add APS and TEMED, then pour the gel and a little bit doesn't polymerise? If so this may be because your gels are not de-gassed and O2 inhibits the polymerisation of acrylamide. Or it could mean that your APS is a bit old, try making some fresh solutions. APS will keep in the freezer for about 6 months.


What do you mean by extra? Is it the solution left behind after you pour your gel? Then is your gel ok? If you gel is ok it's not a problem I suppose?

If you gel is not set, first make sure you mix the solution gently to minimize air in your solution (as bob stated the reason), or you may go for de-gasing (Never done this before but if gas is a real problem) . Then check your APS (this is the most likely part that causing un-set gel), prepare a new 10%APS if needed. Once I found my APS powder looked hydrated and my gel didn't set even I prepared APS solution fresh. I borrowed APS powder from other and it worked fine. Then check Temed and Acrylamide.