377 gels

[George F. Mayhew]

In article <4mcvno$m85 at net.bio.net>, Rick Wilson
<rwilson at watson.wustl.edu> wrote:

::Marc Woodland <m.p.woodland at ic.ac.uk> wrote:
::
::>I  would  love  to  pour  gels  for  my  377  and  leave  them  for  longer
::>than  6  hours -  like  overnight  !  According  to  the  bible  this  is
::>not  possible  for  two  reasons (1) drying  out  of  the  very  thin  gels
::>and (2) hydrolysis  of  urea  to  ammonium  carbonate.  Presumably  it
::>would  be  possible  to prevent  drying  out  by  wrapping  the   top  and
::>bottom of  the  gel  in  clingfilm. But  if  the gel  is  placed  in  a
::>cold  room is  the  rate  of  urea  hydrolysis  slowed  sufficiently    to
::>ensure  a  good  gel  ?  Does  anyone  have  any  ideas,  comments,  or
::>experience  ?  If  so  please  let      me  know.
::
::When you don't like the way things are, start your own religion.  We
::routinely pour gels on Friday and use them on Saturday and Sunday.  The
::key is to wrap both ends with a bit of Saran Wrap so they don't dry out.
::We leave them at room temperature.  Urea hydrolysis does not seem to be
::a problem.  All gels are currently made with pre-made mix from either
::Amresco or Sooner Scientific.
::
::Happy sequencing,
::Rick

I agree with Rick.  We use LongRanger gels with 6M urea.  We cover both
ends with a little saran wrap and leave them overnight for the next
morning.  At present, we do not leave the gels sit longer than ~18 hours.

BTW, putting the gels at 4 degrees might cause the urea to crytalize out.

--
"People are DNA's way of making more DNA."(Edward O. Wilson, 1975)
\ / \  \ / \  \ / \  \ /   George Mayhew   \ / \  \ / \  \ / \  \ 
 \  /\  \  /\  \ E. coli Genome Sequencing Project \  /\  \  /\  \
  \/  \__\/  \__\mayhew at midgaard.genetics.wisc.edu__\/  \__\/  \__\