Casting 3% agarose - Question on melting (Feb/16/2011 )

Hello everyone. I have to use a 3% agarose gel in one of my protocols. The problem is that the agarose congels way too fast, so I have to pour it on the tray while it is hot, but these causes internal cracks to the tray. Does anyone know a trick in order none of these things to happen? Thanks in advance

-Eleni_80-

If it's not the too hot temperature itself causing the cracks, but the temperature differences between hot gel and cold tray (leading to tensions within the tray material), you might preheat the tray slowly e.g. in a water bath.

-hobglobin-

get a better gel casting tray. i always pour hot agarose and the trays are stable.

-scolix-

Use low melting point agarose.

-bob1-

Hello thanks for the replies guys...well my major problem is not the tray so much as the quality of the gel...congeling to fast (even if the agrose reaches boiling temp)...frustrating I get uneven gels, it congels really fast specially on the surface and the walls of the flask....

-Eleni_80-

How cold is your lab? If your lab is cold perhaps you can pour the agarose in a warmer area so it doesn't cool so fast. Can you use a polyacrylamide gel instead?

-proteaSusie-

High percentage gels may not be fully dissolved. Make sure you hydrate the agarose by mixing well with buffer for 1/2 hour or so before boiling it. Make sure it fully dissolves (solution is crystal clear). Use a water bath to cool it to 60-70C or so (it should still be liquid). You may want to switch to using a Nusieve 3:1 agarose, which will work better and be easier to handle.

-phage434-

I use a microwave to heat the agarose/buffer mixture. Since it requires more time to fully dissolve all the agarose, I put a weight boat on the flask to avoir excessive evaporation that would increase the %. And, yes, Nusieve would be better.

-Maddie-