Janet Braam braam at RICE.EDU
Tue Apr 14 09:39:06 EST 1992

In article <12063.9204130857 at subnode.susssys1.rdg.ac.uk>, skspoidn at susssys1.rdg.
ac.uk (Mike Poidinger) writes...
>I am trying to redissolve DNA which has been glass-rod-extracted
>according to protocol 3 from Sambrook/Maniatis, and the %$#@ material
>wont dissolve, wont even come off the glass rod. I am trying to prepare
>medium sized genomic DNA from cell monolayers for southern Hybridization.
>Any ideas on
>a) Getting the DNA off the glass or
>b) A better procedure for DNA preparation
>would be greatly appreciated
>Thanks in advance,
>Mike Poidinger
>Dept of Microbiology
>University of Reading

MIke, the DNA should be easier to dissolve at a slightly alkaline pH, (>pH8.0).  
If there is not enough buffering capacity, your solution may be below pH8.0, 
and this reduces the solubility of the DNA.  Try resuspending in a buffer
with a higher pH; after it is in solution (it may still take an overnight 
incubation), adjust the pH back to neutral.
Janet Braam
Dept. Biochemistry and Cell Biology
Rice University

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