DNA purification from polyacrylamide gels / kits?

[Paul N Hengen]

Harry.Witchel at bristol.ac.uk wrote:

>| I am looking for a KIT for DNA purification from polyacrylamide gels.
>| I know the procedure in the Red Book, but does an even easier one 
>| exist? 
>| 
>| All the kits for DNA purification from gels that I've seen 
>| are designed for agarose.
>
> A kit?!??? >:^{
>
> Electroelute it against 6,000-8,000 MW cutoff dialysis tubing in TBE.
> This gives me nearly 100% recovery of 50-200 bp DNA. Build your own
> device or use the eppi-tube technique. References are in here. Grab
> it at my FTP site.

: I have found crush-elution to be extremely effective for getting DNA 
: of ligation quality (size 50-200 bp) out of 8% acrylamide minigels, and crush 
: elution is both easier and cheaper than every other technique.  The important 
: .               ^^^^^^     ^^^^^^^
: step is that the acrylamide chip be extremely well macerated.  The steps are
: 
: 1)  Macerate chip (explained in a moment)
: 2)  Add 200 ul of TE
: 3)  Vortex well and, Incubate overnight at 37C
: .                    ^^^^^^^^^^^^^^^^^^^^^^^^^
: [...rest deleted...]

Harry:

I think your technique is much more time consuming. You can electroelute
in less than an hour from polyacrylamide gel slices. The cost is also
minimal...not even a factor when considering the amount of TBE buffer
used and a 2 cm square of dialysis tubing. You cut the bottom off an
eppi-tube and wrap the dialysis square onto it using parafilm.

-Paul.

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* Paul N. Hengen, Ph.D.                           /--------------------------/*
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