Best way to get DNA from gel bands?

Thu Jul 27 12:02:30 EST 1995

In article <myersm-2507951347500001 at>,
myersm at (Michael Myers) wrote:

> My current method: QIAquick from Qiagen. Faster than their Qiaex bead
> method. Gel slice is melted in chaotropic salt (probably NaI), then spun
> through a dna binding filter in a microfuge. Washed once, then eluted into
> 30 microliters of water or TE. It takes about 15 to 20 minutes, depending
> on how big your gel slice is. Advantage here is that the eluted DNA is in
> a small enough volume (and presumably free of EDTA) that you can proceed
> with labeling or ligation rxns, no need to ethanol precipitate.

It is a pleasure to hear from a happy user like yourself, and we are 
impressed by your knowledge of our QIAquick and QIAEX for gel extraction
agarose. Please allow us to clarify one point. 

Neither our QIAquick Gel Extraction nor QIAEX II contains  NaI to melt the 
gel slice. We designed our QX1 buffer to eliminate NaI, because NaI is 
difficult to get rid of, and residual NaI may reduce  the efficiency of 
downstream enzymatic reactions such as blunt-end ligation. In addition, NaI

is sensitive to light (that's why most  solubilization buffers are 
stored in a brown bottle and our QX1 is not), therefore you cannot
your DNA with a spectrophometer if the DNA contains residual NaI.

Thank you for your support, 

QIAGEN       800-362-7737
Temporary Email Address          qiagen at

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