Insulator-based dielectrophoresis

Recently there has been an increasing interest in the development of laboratories machined on microdevices (lab-on-a-chip). These portable microsystems would be able to accomplish the same tasks as conventional laboratory equipment, with the advantage of being faster and requiring a smaller sample volume. Thus, separation techniques on a microscale are acquiring a greater importance. Among these techniques, we can find the separation of particles by a dielectrophoretic force. Dielectrophoresis is an electrokinetic transport mechanism that occurs in the presence of a non-homogeneous electric field. Dielectrophoresis is a non-destructive technique with great potential for the separation and concentration of bioparticles. Insulator-based dielectrophoresis makes it possible to trap and concentrate particles inside a microchannel by applying an electric field. The magnitude of the dielectrophoretic force depends on the operating conditions: insulating structures geometry, electric field intensity, particle concentration, conductivity and pH of the suspending buffer. This work presents a parametric study on insulator-based dielectrophoresis with the objected of characterizing the performance of a dielectrophoretic microdevice, and obtaining the optimal conditions for the concentration and separation of a mixture of particles.