Electrophoresis : The existence of charge on colloidal particles is confirmed by electro- phoresis experiment.
When electric potential is applied across two platinum electrodes dipping in a colloidal solution, the colloiclal articles move towards one or the other electrode. The movement of colloidal particles under an applied emf is called "electrophoresis" .
`to` Positive charged particles move towards the cathode while negative charged particles towards anode.