Research Of Microfluidic Chip Based On Electroosmotic Flow Driven By Dielectric Breakdown

Microfluidic chip is a technology which integrates experiment units in terms of sampleintroduction, sample separation, analysis etc. on a single chip through micro-pump, microvalve and other components. It started from1990s and has become a global frontier science.It wildly applied in analytical chemistry, biology, clinical medicine, environmentalmonitoring, information science etc.Electroosmotic flow is a vital control technology of microfluidic chip. It utilizesCoulombian forces to drive the fluid directly by affecting on double electrode layers of thechannel wall. Micro-pumps and micro volves etc are unnecessary in electroosmotic flow soit benefit the integration and miniaturization of the microfluidic devices.The paper designed a microfluidic chip based on electroosmotic flow driven bydielectric breakdown. The methodology of the chip is to place a tip between two connectedchannels as a blocking layer and drive the fluids in the channels through dielectricbreakdown of the tip. The paper mainly designed the feasibility of driving electroosmoticflow by dielectric breakdown in micro-scale. It aims to replace electrode by conductiveliquid in channels to simplify the integration technique of microfluidic chip. The designmethods are considering simulation results of distributions of electric field, joule heatingand temperature during dielectric breakdown by COMSOL multiphysics software and theheat tolerance of channel materials to the reversibility of dielectric breakdown. Through thesimulation results of distributions of the fluidic velocity and pressure, it can conclude therationality of electroosmotic flow driven by dielectric breakdown and the electroosmoticflow pump of switching type of micro-channels.The paper also designed a methodology which compares two type of channels totesting the efficiency of electroosmotic flow driven by dielectric breakdown. One is with atip blocking fluids in the channel, the other is throughout channels. Then the paper selectedpolydimelthylsiloxane (PDMS) and silica as raw materials to fabricate microfluidic chipthrough lithography, photoetching, bonding with ultraviolet and other techniques. At last,we detected electroosmotic flow through observing the movement of cells.