Greetings.

I am trying to perform a gelatin zymography, however, I keep obtaining the messed "П"-shaped bands (please, see the images attached), instead of the straight horizontal bands.

Could anybody please explain why the bands turn out to be so messed? and what could be done to improve them?

(I use conditioned, 10x concentrated (with SpeedVac vacuum concentrator) medium from cells)

Many thanks for the advice!