Improvement Design of Biochip Towards High Stable Bioparticle Detection Utilizing Dielectrophoresis Impedance Measurement

摘要

Dielectrophoresis impedance measurement (DEPIM ) is a powerful tool for bioparticle detection due to its advantages of high efficiency ,label-free and low costs .However ,the strong electric field may decrease the viabili-ty of the bioparticle ,thus leading to instability of impedance measurement .A new design of biochip is presented with high stable bioparticle detection capabilities by using both negative dielectrophoresis (nDEP) and traveling wave dielectrophoresis (twDEP) .In the biochip ,a spiral electrode is arranged on the top of channel ,while a detec-tor is arranged on the bottom of the channel .The influence factors on the DEP force and twDEP force are investi-gated by using the basic principle of DEP ,based on which ,the relationship between Clausius-Mossotti (CM) fac-tor and the frequency of electric field is obtained .The two-dimensional model of the biochip is built by using Com-sol Multiphysics .Electric potential distribution ,force distribution and particle trajectory in the channel are then obtained by using the simulation model .Finally ,both the simulations and experiments are performed to demon-strate that the new biochip can enhance the detection efficiency and reduce the negative effects of electric field on the bioparticles .