eluation of small DNA fragments from gel

Johns053 at mc.duke.edu Johns053 at mc.duke.edu
Wed Feb 23 12:26:20 EST 2000

I do this fairly routinely using the EluTrap from S&S.  If you want a low tech
version of this, do the old-fashioned electroelution into a dialysis bag using a
low molecular weight cut-off bag.

Matthias Wahl <matthias.wahl at gsf.de> on 02/23/2000 12:12:37 PM

To:   methods at hgmp.mrc.ac.uk
Subject:  eluation of small DNA fragments from gel

Could anyone tell me a good method for eluting small DNA fragments
(20-30bp) from Polyacrylamide? It could also be a method for eluting
from Agarose (Metaphor etc). My problem is, that most methods use
temperatures, at which such small fragments will melt.

I currently use 12% PAGE, and elute just by incubating together with
buffer for >2h at 37
-------------- next part --------------

?C and afterwards just filter away the
polyacrylamide. My problem is that I only have a very low efficiency in
a subsequent ligation step. Propably I carry over some contamination
from the polyacrylamide. Is this likely that remaining polyacrylamide is
inhibiting ligation reactions, or do I just have some impure reagents
for making the gel.

I also looked for some commertial kits for purifying the eluted DNA but
they are not suitable fur fragments of this size.

Thanks in advance

Matthias Wahl

More information about the Methods mailing list