Abstract: A method for concentrating electrically charged objects in a non-Newtonian liquid medium comprises: feeding a sample containing electrically charged objects into a channel having a flow axis, a first transverse cross-section orthogonal to the flow axis, and at least one second transverse cross-section orthogonal to the flow axis, one dimension of the second cross-section being less than the corresponding dimension of the first cross-section; and applying a hydrodynamic flow in a direction of the channel together with the application, in the opposite direction, of an electric field in the channel, thus making it possible to move the electrically charged objects in the channel along the flow axis from the first cross-section to the second cross-section, stop the objects, and concentrate the objects in at least one area upstream from the second transverse cross-section.

Abstract: A method for separating a plurality of deformable objects, such as biological cells or biological supramolecules such as DNA, in a liquid medium by use of an electrophoretic technique combined with hydrodynamic forces. The deformable objects are introduced into a channel, having a flow axis and a cross section at right angles to the flow axis, with the minimum size of the cross section being less than or equal to 50 pm; A hydrodynamic flow is defined a in the channel together with the application of an electric field in the channel, making it possible to move the deformable objects in the channel according to the flow axis and to separate them along the flow axis. A device suitable for implementing this method. The electrolyte used for the electrophoretic separation may be a non-Newtonian fluid with viscoelastic properties.

Abstract: A method for concentrating electrically charged objects in a non-Newtonian liquid medium comprises: feeding a sample containing electrically charged objects into a channel having a flow axis, a first transverse cross-section orthogonal to the flow axis, and at least one second transverse cross-section orthogonal to the flow axis, one dimension of the second cross-section being less than the corresponding dimension of the first cross-section; and applying a hydrodynamic flow in a direction of the channel together with the application, in the opposite direction, of an electric field in the channel, thus making it possible to move the electrically charged objects in the channel along the flow axis from the first cross-section to the second cross-section, stop the objects, and concentrate the objects in at least one area upstream from the second transverse cross-section.

Abstract: A method for separating a plurality of deformable objects, such as biological cells or biological supramolecules such as DNA, in a liquid medium by use of an electrophoretic technique combined with hydrodynamic forces. The deformable objects are introduced into a channel, having a flow axis and a cross section at right angles to the flow axis, with the minimum size of the cross section being less than or equal to 50 pm; A hydrodynamic flow is defined a in the channel together with the application of an electric field in the channel, making it possible to move the deformable objects in the channel according to the flow axis and to separate them along the flow axis. A device suitable for implementing this method. The electrolyte used for the electrophoretic separation may be a non-Newtonian fluid with viscoelastic properties.