Microelectrophoresis is a method of studying electrophoresis of various dispersed particles using optical microscopy. This method provides image of moving particles, which is its unique advantage.
Complexity of this method is associated with electro-osmosis generated by electric field influence on the double layers of the sample cell walls. In the usually used closed cells this creates Poiseuille type back flow, leading to parabolic velocity profile. There are two stationary layers, where fluid does not move. Position of these stationary layer regarding cell walls depends on the cell geometry. It is possible to focus microscope on this stationary layers and observe particles motion not affected with electro-osmosis.
The second complexity comes from necessity of diluting sample, if it was initially concentrated. Concentration must be sufficiently low for observing individual particles.