[NHCOLL-L:4509] RE: resitivity for water used in wet collections?

[Dirk Neumann]

Dear Ludovic,

YES; depending on the denaturing agent, how polar it is and for how long 
the tissue are stored in the denatured alcohol. An exemption would be 
Isopropyl alcohol as denaturing agent.
Polar additives tend to degrade the DNA-helix, resulting in low quality 
row-DNA extracts and short fragments reading frames after amplification, 
so that internal primer might be necessary.

The same obviously applies for highly concentrated (technically dried) 
absolute Ethanol  (e.g. 99.8 %). Residual Benzines used for water 
extraction above Ethanol concentrations of 96% seems to degrade the DNA, 
too. We had problems with tissues after being stored for 1 year in 99.8 
% Ethanol. We changed our tissue collection to (destilled) Ethanol 
(96%). This concentration is sufficient for DNA preservation & storage 
if you don't exceed the ration 1:3 for initial preservation (1 part 
tissue, 3 parts Ethanol).

Hope this helps
Dirk


BESSON Ludovic schrieb:
>
> Is it a problem when you used for your wet collection denatured 
> alcohol? Is it a problem for future DNA analyse ?
>
>  
>
> Best regards
>
>  
>
> Ludovic Besson
>
> Responsable des collections
>
> Muséum Gabriel Foucher
>
> Les Rives d'Auron - Allée Ménard
>
> 18000 Bourges (France)
>
> Tél.: 02 48 65 37 34
>
> http://www.museum-bourges.net/
>


-- 
Dirk Neumann

Tel: 089 / 8107-111
Fax: 089 / 8107-300
email: Dirk.Neumann(a)zsm.mwn.de

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---------

Dirk Neumann

Tel: +49-89-8107-111
Fax: +49-89-8107-300
email: Dirk.Neumann(a)zsm.mwn.de

postal address:

Bavarian Natural History Collections
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