Wave-shaped electrode design for enhanced nanowire alignment efficiency: A comparative analysis with interdigitated electrodes in two-dimensional plane

The dielectrophoretic (DEP) force acting on micro- and nanoparticles is highly dependent on the gradient of the electric field experienced by the particles. The DEP force enables the selective capture and removal of micro- or nanoscale particles from the fluid flow within the microchannels. Designing the geometrical structure of electrodes to increase the electric-field gradient within a 3D microfluidic channel is important in particle classification and alignment applications. In this study, we evaluated the particle alignment performance of wave-shaped electrodes, a modified geometrical form of conventionally used interdigitated electrodes, by calculating the DEP force experienced by particles within a microfluidic channel and analyzing the force in both the in-plane (xy) and out-of-plane (xz) directions. The particle alignment efficiency of both electrode forms was evaluated using finite element analysis and nanowire alignment experiments in an actual microfluidic channel environment.