Thread: SDS Page

Dear Everybody,
I tried to run a sds-page gel, but always it appears a curve in the gel and below of this curve the sample doesn't run and above the sample runs but respect the form of the curve. Sometimes this curve appear more intesity like a statistical normal distribution. It is something wrong with the composition of the gel or I should change the voltage.What is better run in a constant voltage or amperage?

Thank You
Rosangela