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Stability of genomic DNA in 1x PBS - (May/18/2010 )

Hi all

I perform heat-induced genomic DNA extraction from bacterial cells, and at the end they are stored in 4C in 1x PBS. I would like to know if there is any data/paper showing the duration in which they are stable for.

This article from QIAGEN shows that using their Buffer AE purified DNA is stable for up to 8 years in 2-8C. However, of course, the chemical makeup of AE is different from PBS.

Thanks all


Two major things affect DNA stability, pH and lack of magnesium. TE is designed with pH 7.5 to 8.0, and with 1 mM EDTA, to remove residual Mg++ ions. DNA is stable in TE almost indefinitely at 4C (actually, at room temperature also). I would assume that the E in AE is also EDTA. I don't know the other component, but it is likely a buffer for pH control also.


See Qiagen's FAQ no. 730 here:


730 What is the composition of buffer AE?


The composition of Buffer AE is:

10 mM Tris-Cl
0.5 mM EDTA; pH 9.0.

Buffer AE is the elution buffer used in DNeasy Kits for genomic DNA isolation from animal and plant samples, and QIAamp Kits for DNA isolation from clinical samples.