Numerical design of a 3-D microsystem for bioparticle dielectrophoresis: The Pyramidal Microdevice

A device for the detection of bioparticles (latex beads, cells, proteins, DNA,…) present in a small volume of a liquid sample is described. Dielectrophoresis (DEP) is used to enhance the transport of bioparticles towards the reactive surface of the detector. A Pyramidal Microdevice (PM) is designed using numerical simulation. Unlike conventional coplanar electrode microchips, this original 3D configuration is able to collect particles on a surface for both positive and negative DEP. Numerical simulations show the location of the collection zones in the PM according to the DEP mode applied. PM performance is evaluated with the calculation of the collection kinetics. The influence of the voltage is studied. Experiments on PM with latex microparticles confirm calculations. Their replacement by DNA molecules attests to the feasibility of a PM collecting such extremely small particles using DEP.