Glycerol PAGE "toughening"

[David L. Haviland, Ph.D.]

At 19:35 6/16/99 GMT, Warren Gallin wrote:
>In Article <7k8mat$q7k$1 at nnrp1.deja.com>, stebby at welchlink.welch.jhu.edu 
>>I can't address the question of truth, but the lab I post-doc'd in
>>routinely used 5% glycerol in the separating gel and it certainly didn't
>>hurt.  I've continued this "tradition" in my work for the last 7 years
>>for consistency if nothing else.  As I recall in a side by side
>>comparison my first few weeks in the new lab I noticed slightly tighter
>>bands in coomassie stained gels containing the glycerol.  I'll avoid the
>>obvious jokes and simply say that I don't recall them being "tougher".
>
>    Adding glycerol or sucrose to the separating gel mix will make it much
>easier to layer water on top of it to level out the upper surface.  It is
>not necessary, but you will get less mixing of the overlay and the gel, so
>later, when the stacker is poured on top, the interface between the two is a
>little sharper.  That could contribute to a slightly sharper band.
>    I couldn't comment on whether there are other effects.


Warren:

I can't help but ask if the inclusion of 5% glycerol also improved the
drying, and less cracking of high percentage gels... i.e., greater than
12-15%?    I've had little problem with fixed and gradient percentage gels
up to about 12.5% but above that, they start cracking.

Curious,
David
=============================
 David L. Haviland, Ph.D.
 Asst. Prof. Immunology 
 University of Texas - Houston, H.S.C.
 Institute of Molecular Medicine  
 2121 W. Holcombe Blvd.  
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 Internet:"dhavilan at imm2.imm.uth.tmc.edu" 
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