微通道内非对称诱导电渗流与定比例颗粒聚集

Asymmetric Induced-charge Electroosmosis and Proportional Particle Trapping in Microchannel

针对生化检测仪器传统样品处理过程中的耗量大、时间长等问题,设计了基于诱导电渗的微流控芯片,利用微通道内的非对称电渗漩涡实现宽、窄电极上浓度成比例的颗粒聚集。采用COMSOL求解非对称漩涡的流动特性与颗粒的受力,提出了适宜颗粒聚集的理想滑移速度轮廓。通过研究主要参数对滑移轮廓的影响,预测了芯片的工作区间。实验证明:在此区间内,颗粒聚集比例与电极宽度比一致,且响应快速,易于调控,可进一步生成多级浓度颗粒流。

A microfluidic chip using induced-charge electroosmosis（ICEO） was proposed according to the problem that the consumption is big and time is long in the process of biochemical testing instrument traditional sample process,where the asymmetric ICEO vortexes trap particles with proportional concentration assembled above wide and narrow floating electrode.Asymmetric vortex flow characteristic and the stress of the particles were solved in COMSOL.Ideal sliding velocity profile suitable for particle aggregation was put forward.Based on the slip velocity profiles under various conditions,an effective slip velocity profile and the corresponding operating range were provided.The experiments validate that the particle-trapping ratio approaches the electrode width ratio,which has superiorities of quick response and ease in control,inspiring further study on generating discrete concentrations of particle flow.