polyacrylamide-agarose gel

[Virginia Dress]

In article <9406012128.AA16466 at acs2.acs.ucalgary.ca>,
llintott at ACS.UCALGARY.CA ("Lauri Lintott") wrote:
> 
> Has anyone out there ever used vertical acrylamide-agarose gels?
> I am trying to make a 3.5% acrylamide/0.5% agarose gel but I am
> having 2 problems.  First of all how do you keep the gel from
> slideing out?  I have tried using a 2% agarose wedge at the
> bottom but this was unsuccesful.  Secondly, how do you get the
> comb out without the wells collapsing?
> One more question, do the spacers have to be thicker than the
> comb as is stated in the only procedure I can find (R. H. Nicolas
> in Gel Electrophoresis of Nucleic Acids:A Practical Approach.
> 1990.  Ed. D. Rickwood and B.D. Hames).
> Any advice would be appreciated.
> 
> Lauri

a colleague of mine used to do agarose-acrylamide gels and that required
that
one of the glass plates be frosted to keep the gel from sliding out.  We
were
using the Hoefer SE600, I know they sell frosted glass plates for their
rig.
If you are using the Hoefer mini-gel system, one plate is alumina and would
act
like the frosted plate to keep things from sliding.  She was separating
glycoproteins.
	I don't remember her having trouble with the comb, but my intuition tells
me
that the answer to your question on how to get the comb out is   v-e-r-y
c-a-r-e-f-u-l-l-y .  Try to pull it up slow and straight, maybe with a
little
wiggling back and forth (not side to side across wells) to let some air in
so
as not to create a vacuum.  Maybe adding some buffer around the top so that
the liquid runs in to the wells may help.

Ginnie