Electroosmotic flow is the motion of liquid induced by an applied potential across a porous material, capillary tube, membrane, microchannel, or any other fluid conduit.

What is electroosmotic flow Why does it occur?

Electroosmotic flow occurs because the walls of the capillary tubing are electrically charged. The surface of a silica capillary contains large numbers of silanol groups (–SiOH). At pH levels greater than approximately 2 or 3, the silanol groups ionize to form negatively charged silanate ions (–SiO^–).

What is electroosmotic flow in capillary electrophoresis?

Electroosmotic flow is observed when an electric field is applied to a solution in a capillary that has fixed charges on its interior wall. ... The mobile cation layer is pulled in the direction of the negatively charged cathode when an electric field is applied.