how to interpret native gel result - (Nov/11/2005 )

Hi, folks,
I ran a native gel electrophoresis, but I am not sure how to interpret it.
Can I decide the relative sizes by the relative positions of proteins on the gel?
My concern is that the protein samples are not denatured, so I have to take into account of the charge property for analysis. Then it's really hard to say about the MW, right?
Thanks.

PS
I am physicist, but doing biochemisty.

Hi, I am not an expert in native gels, but this website seems useful... You could determine which protein is which by transferring the gel to a membrane and doing the equivalent of a western blot... I think it will be difficult to determine MW...

http://www.ap-lab.com/native_gels.htm

Hope this helps..