Numerical Investigation of the Correlation between Electrode Structure and Number of Captured Particles in a Dielectrophoretic Device

Abstract

SUMMARYFor the strict application of food hygiene regulations such as hazard analysis critical control point systems, the development of a rapid and simple measurement scheme for biological particles is essential. Recently, a hybrid method using dielectrophoretic manipulation and microfluidic operation has attracted attention for bioparticle detection. However, the influence of the electrode structure on the dielectrophoretic force has not been fully understood. For effective design of dielectrophoretic devices, it is important to investigate quantitatively the capture characteristics. In the present work, we numerically simulate the particle dynamics in the capture region of a dielectrophoretic microdevice with interdigitated electrodes. The dependence of the dielectrophoretic force on the electrode width and gap length shows that there is a maximum for the capture height of particles, assuming an adequate electrode structure. Furthermore, the number of captured particles is accurately evaluated when the effective region ratio is taken into consideration. Under typical conditions, the number of captured particles is almost always in agreement with experimental results.