Maxiprep troubleshooting - There are 3 bands in CsCl gradient after ultracentrifuge (Aug/20/2008 )

I performed Maxiprep using CsCl/EtBr method. However, after ultracentrifuge, I saw 3 bands. I don't know what the lowest band is.
Please help me!!!
Thank you very much

-huongdalan-

I have never used that method, but why use ultracentrifuge, etc. There are much simpler protocols. I will be happy to send you one if you need.

-UGA80-

QUOTE (huongdalan @ Aug 20 2008, 05:14 PM)

I performed Maxiprep using CsCl/EtBr method. However, after ultracentrifuge, I saw 3 bands. I don't know what the lowest band is.
Please help me!!!
Thank you very much

you could have chromosomal DNA , then nicked plasmid?! and supercoiled plasmid.

-Hanming86-