4 replies to this topic

[saara]

I am trying to extract DNA bands from 4% acrylamide gel, but I had no success. Does anybody thinks that the age of acrylamide gel (my gel stock solution is about a year old) can affect the extraction of DNA bands from the gel.

[ShannonJ]

In my experience, the acrylamide (if stored at 4C) should be fine. We also never "extracted" DNA from the gels, just cut the bands and placed them into 10mM Tris for 24-48hrs in the fridge. Over that time most of the DNA escaped from the gel into the liquid...at least enough for PCR. Hope that helps.

saara, on Nov 1 2009, 02:23 PM, said:

I am trying to extract DNA bands from 4% acrylamide gel, but I had no success. Does anybody thinks that the age of acrylamide gel (my gel stock solution is about a year old) can affect the extraction of DNA bands from the gel.

[Mulletman]

ShannonJ, on Nov 2 2009, 04:01 PM, said:

In my experience, the acrylamide (if stored at 4C) should be fine. We also never "extracted" DNA from the gels, just cut the bands and placed them into 10mM Tris for 24-48hrs in the fridge. Over that time most of the DNA escaped from the gel into the liquid...at least enough for PCR. Hope that helps.

so we don´t need to use the gel extraction kits?
Awesome cost saver....

[ShannonJ]

I always have for agarose gels but not for acrylamide...but like I said you had to let 'em sit in the fridge for at least a full day. You might get better recovery with an extraction kit but we were just re-PCRing from DGGE gels and it worked pretty much without fail.

Mulletman, on Nov 3 2009, 05:04 AM, said:

so we don´t need to use the gel extraction kits?
Awesome cost saver....

[Quasimondo]

Did you succeed? I did that in the past. In my case it's the 6% acrylamide. I just cut out the band, place them in water, grind and boil for 15 minutes (the gel won't be dissolved but the acrylamide matrix can be loosen a little bit and DNA can escape to the medium). It's enough for PCR.