Wick flow is caused by the movement of the buffer into the support medium. Moisture evaporation from the gel caused by heat generation during electrophoresis causes the buffer to move into the gel. The gel absorption of the buffer to replace the lost moisture affects the migration of sample molecules.
Using a lid or cover during electrophoresis can prevent some of this evaporation. Methods that generate excessive heat utilize a cooling system during electrophoresis to prevent wick flow and other damage to sample solutes.
