Dielectrophoretic characterization of microorganisms employing three dimensional carbon electrodes uri icon


  • Dielectrophoresis is electrokinetic transport mechanism that has been successfully employed to manipulate particles in microfluidic devices. Several applications have been demonstrated using planar metallic electrodes or insulating obstacles; which until now had been the two main trends on dielectrophoretic devices. The use of 3D electrodes in DEP applications has attractive advantages: since it allows for higher separation throughputs and requires lower electric potentials than the traditional planar electrodes or insulating structures approaches. Carbon-based-electrode Dielectrophoresis (CarbonDEP) is a novel technique that employs 3D carbon structures or surfaces as electrodes with advantages that make it a more suitable material than those traditionally used in metal-electrode DEP. One of the most promising techniques for carbon microfabrication is that of Carbon MicroElectroMechanical Systems (CMEMS). Presented here is the implementation of a bioparticle characterization platform based on CarbonDEP. A microdevice containing arrays of 3D carbon electrodes was employed to manipulate carboxylated polystyrene particles and yeast cells in order to characterize cell dielectric properties. Cells responses were obtained by varying the magnitude and frequency of the applied AC potential as well as the characteristics of the suspending medium. Simulation work allowed building a model to predict cells responses. These results have the potential to be used as guidelines for the design and operation of CarbonDEP-based systems. Potential applications include clinical analyses, environmental screening for water contamination, and optimization of cell culture techniques, improvement of clean energy production methods and food safety methodologies and procedures.

Publication date

  • December 1, 2010