melted agarose gel

[Kairi1903]

Hi
Can melted agarose gel containing DNA be frozen again..without damaging the DNA?
Thx

[butters]

Well, are you using low melting agarose or high melting agarose?

What is the purpose of your question?

[Kairi1903]

Hi
It's actually high melting point. I had the DNA band in the agarose gel which i isolated to do a DNA precipitation. But before the precipitation i froze it. Does this freezing have any bad affect ?

[marcusho]

agrose gel has a low freezing temperature it'll solidify fast if you keep it in the 4' fridge, so i would think the DNA wouldn't get degraded as long as you don't freeze and melt it many times.

i assume you're trying to use a gel extraction kit to get a small amount of DNA out? if so that seems pretty damn hard to do and you wil probably get a low yield dependin on how much DNA you loaded in the well in the first place. you're better off running a new gel and not letting it melt. run it on lower voltage for longer time.

-dna is stable @ -20'C and takes at least 95'C to anneal so don't heat the gel any higher than that temperature.

[Biology Homework]

DNA might lose its form and structure if it is exposed to varied temperatures. Since you want to do a precipitation experiment i guess the DNA would be centrifuged, so exposing the DNA to varied temperatures and then centrifuging might cause damage to the DNA resulting in a lower yield.

[butters]

Kairi1903, are you doing the freeze squeeze method? as [Only registered users see links. ]

If your protocol is as suggested. You should carry on.

[qianhaha]

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