Continuous particle separation of microfluidic chip with integrated inertial separation and dielectrophoresis separation

Particle separation is essential in many microfluidic systems such as biomedical analysis and chemical reactions. This study aims to report a microfluidic separation device combining dielectrophoresis force and inertial force to separate particles continuously. Most particles were separated by inertial force via passing through the contraction and expansion channel and then deviated into different outlets via interdigital electrodes. Numerical simulations using the software COMSOL Multiphysics 5.4 were performed to investigate the effects of flow rate and electric field distribution on particles. The separation efficiency was assessed by separating 4 µm polystyrene spheres (PS) from 20 µm PS microspheres at various flow rates. The experimental results showed that the separation efficiency was more than 95%. This microfluidic chip is expected to be applied to cell sorting and biomedicine.