DNA elution from agarose-gel

[Dr. Hiranya S. Roychowdhury]

About a decade back, on the usenet groups, I had posted the modified method of 
centrifugal extrusion of larger DNA pieces.  Type in my name and see if you can 
find it.  Otherwise let me know again I will write it up once more.  I have 
never seen a protocol uising HybondN for DNA re-elution, and I don't know that 
you can do it from a +vly charged nylon; the interaction seems to be quite 
strong.  I thought the DEAE membranes were not available anymore! However, 10-
15kb DNA will not elute out of even DEAE membrane at more than 30-50% recovery. 



Quoting Dirk Müller <Kraweel at web.de>:

> We have a severe problem with eluting restircted DNA (10-15kb) from
> agarose gel. We have already testet QiaexII, Genomic purification kit
> from Promega, Gel elution colums from Microcon, and electroelution but
> don't get more than 1-10 % of the initial DNA which is not enough for
> downstream methods. Using electroelution we can elute the complete DNA
> into the membrane(DEAE or hybond N/N+) but we can not elute the DNA
> from the membrane in the elution buffer (15 min at 65°C in 2 M NaCl,
> 10 mM Tris/HCl pH 7 (pH 7-8), 1 mM EDTA). I would welcome any hints
> from this news grout that  will will help with this problem.
> thank you, Dirk...
> 


-- 
Hiranya S. Roychowdhury, Ph.D.
Coll. Asst. Professor,
Molecular Biology,
Dept. of Chemistry & Biochemistry
Rm# 336, Chemistry Bldg.; MSC 3MLS
New Mexico State University
Las Cruces, NM 88003
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