Design and Performance of Microdevices for High-Efficiency Sterilization of Bacteria
In this study, devices with micro-scale electrodes are designed for the sterilization of bacteria. Due to much short distance between each pair of electrodes, low voltage pulse electric field can be used to achieve good effect of sterilization. Structures of electrodes and channels are attentively designed for desired electric-field profile, the impact of some electric parameters is also discussed.
COMSOL Multiphysics software is used to simulate the change of trans-membrane voltage on bacteria and the electroporation process. Geometries of electrodes and channels, as well as some electric parameters such as voltage, number, width, interval of electric pulses are investigated. Simulation results show that the electric field can be focused by microelectrode array other than plate electrodes with micro-scale gap. Thus, stronger electric field can be generated within a microelectrode array than that between two plate electrodes under the same applied voltage, and it helps sterilization. For three different microelectrode arrays, planar-comb teeth structure can achieve better sterilization effect. The impact of electric parameters on the generation, amplitude and distribution of trans-membrane voltage on bacteria has also been simulated. Suitable parameters can form perforation with enough size to kill bacteria without overmuch energy consumption and thermogenesis. Experimental studies also obtain similar results as the simulation. Based on the simulation, optimal sterilization device and electric parameters can be achieved.