Dissolving plasmid DNA after precipitation

Kevin A. Mulcahy K.Mulcahy at sheffield.ac.uk
Sat Jan 25 06:47:56 EST 1997

Cheers for your reply.

In your message you wrote:
> How big are your plasmids?  The bigger the DNA, the harder it is to get
> into solution.  A plasmid 2-10Kb should have no problem going back into
> solution quickly, but DNA (such as adeno, 35Kb) can take up to a day to
> do so.

The plasmids/restriction fragments are anything between 1.5 and 10 kbp.
>Any residual EtOH in your pellet will affect it's ability of going back >into solution as well.  I tend to dry my smaller DNA's in a speed vac >to get rid of it all.

How long do you dry the pellets in the speed vac and what size do you 
mean by "smaller DNAs"? Do you dry it until the pellet actually looks dry 
or do you dissolve once all the droplets have disappeared but the pellet 
still looks wet?

Many thanks,


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