Agarose gel bands smear/ drag problem - (Nov/05/2010 )

I am having a problem with my 1.5% agarose gel, where is seems that the bands are dragging???? I have tried fresh TAE buffer for the tank and the gel. I seem to get this problem with my DNA PCR products, of various concentrations and with my freshly made 1kb marker. Any ideas?

Is it smearing or do you get smiley bands. For the latter I would guess it's the heat. Try running at lower voltage to prevent the gel from heating up. For the former it's usually because of degradation in the sample. Do you have an image of the gel, so we can better see the problem.

Thank you. I'm not sure how to descibe it really! im running it at 110V for 2.5hrs. I have just run a 2% e-gel with the same samples and not seen this problem run really need to run it longer for the band differences i am looking for. the attached pic has markers in lanes 1 and 20. thanks again.

I think the agarose is not polymerizing properly in this case. Give it some more time for polymerization.

I don't think the problem is the agarose. I've had this problem myself. In my experience this happened because voltage was too high or because the salt content of the samples was too high. I am guessing that your loading buffer is too concentrated. Try a different loading buffer.
Just my two cents.
Best of luck.
Miha