In certain embodiments a device is provided for electrorotation flow. In certain embodiments the device comprises a microfluidic channel comprising a plurality of electrodes disposed to provide dielectrophoretic (DEP) forces that are perpendicular to hydrodynamic flows along the channel; and a fluid within the channel providing the hydrodynamic flow along the channel; wherein the device is configured to apply focusing voltages to the electrodes that provide an electric field minimum in the channel and that focus cells, particles, and/or molecules or molecular complexes within the channel; and where the device is configured to apply rotation-inducing voltages to the electrodes that induce rotation of the cells, particles, molecules and/or molecular complexes as they flow through the channel.
