Electrophoresis is the process in which sample ions move under the influence of an applied voltage. The ion undergoes a force that is equal to the product of the net charge and the electric field strength. It is also affected by a drag force that is equal to the product of f , the translational friction coefficient, and the velocity. This leads to the expression for electrophoretic mobility:

where f for a spherical particle is given by the Stokes’ law; η is the viscosity of the solvent, and r is the radius of the atom. The rate at which these ions migrate is dictated by the charge to mass ratio. The actual velocity of the ions is directly proportional to E, the magnitude of the electrical field and can be determined by the following equation:

This relationship shows that a greater voltage will quicken the migration of the ionic species.