Simultaneous Separation/Trapping and Dual Trapping of Microparticles in a Novel Microchip using Dielectrophoresis

Particle manipulation using Dielectrophoretic (DEP) force is widely used in microfluidic systems. Because this force is highly sensitive to the electrical properties of particles and the medium as well as the frequency of the electric field. Therefore, regarding the electrical properties of particles and the medium, the attractive and repulsive DEP forces can be created by adjusting the electric field frequency. In this numerical study, two electric fields with different frequencies are employed for simultaneous separating/trapping of particles and dual trapping of particles by taking advantage of the DEP force. At first, by proposing a single-chamber microchannel, the effects of frequency and voltage are investigated for trapping the 5μm Polystyrene particles within the microchannel chamber and for separating and ejecting the 2μm polystyrene particles from the microchannel. At this stage, the optimum voltages are obtained for trapping the 5μm particles and ejecting the 2μm particles according to the obtained performance diagrams. Then, another chamber is added to the microchannel for dual trapping of polystyrene particles. By utilizing the optimum voltages, the particles with different sizes are trapped in different chambers of microchannel. In this section, the performance cartography of the proposed system is also evaluated for the first time to select the optimum values and smart separation. In all numerical simulations, two electric fields with different frequencies are used, one electric field absorbs the particles and the other field repels the particles.