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Smears on agarose gel, contamination? - (Sep/10/2005 )

I had smears on my agarose gel ( DNA)

what could be the reason
too much sample/contamination with RNA/
gel concentration?

what will happen if I run the gel at an increased voltage?

How to preserve the gel ?


What kind of DNA did you load? gDNA, plasmid, PCR products, .....
And it would be helpfull if you could include a photograph of the gel.


iam working with genomic DNA
I would try to get the photo
thanks Theo


which one is better?(for DNA )

Staining the gel with ethidium bromide & running the gel
staining after running the gel?


genomic DNA will result in a big smear down the lane if there is degradation, or if it was over-pipetted or vortexed too much during extraction, causing the DNA to shear into smaller bits

i put etbr directly into the gel when pouring, you don't have to deal with sloshing hazardous waste and proper disposal is much easier...I know a gal who puts a very tiny bit into her loading dye and she says that is really the best

increased voltage is probably not going to help you. if the smear looked like a smiley face in each lane that might be your problem in the first place