Odd problem with sequencing gels

[unknown at dl.ac.uk]

Have you tried a different loading buffer for your samples?  The timing
of the problem would suggest that the problem might be with the samples
rather than the gel.


> 	I am having an odd problem with my sequencing gels that no one around
> the university can offer an explanation for; thus, I appeal to the wisdom of
> the bionet.  My problem is this... when I run a sequencing gel, everything
> begins just fine.  I like to run around 1700V and 40W.  The gel preheats, I
> load it, and then trouble begins.  Over the course of the run, the wattage
> begins to decline (and with it the ampage), although the voltage remains
> constant.  After about two hours, the wattage is down to 25W, and the gel has
> cooled to the point where it is useless for sequencing.
> 	I have changed gel buffer systems (TBE and TEB), changed the way I pout
> my gels, changed the percantages of acrylamide, recirculated the buffer,
> and completely changed the buffer; all to no avail.  The power
> supply appears to be working correctly.  It runs other gel boxes without this
> porblem.  I can generate current across the upper well but NOT through the gel.
> Does anyone have any ideas and/or suggestions as to what is going on?
> 
> Anthony Arment
> Wright State University 
> 

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James F. George, Ph.D.              "Back off man, I'm a scientist"
Department of Surgery                --Bill Murray
University of Alabama at Birmingham
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