Methods and devices for the separation of particles (20, 21, 22) in a compartment (30) of a fluidic microsystem (100) are described, in which the movement of a liquid (10) in which particles (20, 21, 22) are suspended with a predetermined direction of flow through the compartment (30), and the generation of a deflecting potential in which at least a part of the particles (20, 21, 22) is moved relative to the liquid in a direction of deflection are envisaged, whereby further at least one focusing potential is generated, so that at least a part of the particles is moved opposite to the direction of deflection relative to the liquid by dielectrophoresis under the effect of high-frequency electrical fields, and guiding of particles with different electrical, magnetic or geometric properties into different flow areas (11, 12) in the liquid takes place.