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Gel extraction and elution buffer - (Jun/07/2005 )

Hi, there, I am trying to extract and purify DNA from gel by using the Qiagen gel extraction kit. In order to increase the DNA concentration, I am trying to use water to elute the DNA. But I have checked the Ph value of the water, it is below 7.0, what should be added for increasing the Ph? Any suggestion will be appreciated.


Try the elution buffer from other Qiagen Kit (etc. PCR cleaning kit) if ur kit doesn't carry one. By the way, u can even make ur own elution buffer (10 mM Tris-Hcl, PH 8.5).


[quote=syp,Jun 7 2005, 05:32 PM]
The problem is that after elution with the buffer or water, I will put it in the vaccum to evaporate some water for the purpose of concentration. I have tried several times by using elution buffer, but the concentration of DNA is always low, even use 30 ul buffer. I have to increase the volume of DNA loading, but the weight is over the maxmium limit of Kit. so I have to use two column and use two 30 ul to elute the DNA. And then, I wanna put them together and concentrate by using vaccum. so, if I use EB, the DNA solution might contain high Tris. is that right?


to increase the amount of DNA eluted from the column, you can heat the elution buffer or H2O to 70C and then add it to the column.

Once eluted you could ethanol precipitate and then resuspend in a lower volume.



You can also try eluting a 2nd time using the first elutes.