电渗流速度检测研究

Research on the Electroosmotic Flow Velocity Detection

针对微通道的结构特性、微流体的输运特性和电渗流的驱动特点,设计了一种基于微通道内电渗流速度的检测系统,并通过改变液体浓度及外加电压强度,分别实现对电渗流速度的测定。检测系统设计基于电流法监测原理,采用前置放大电路、滤波电路,同时利用MSP430 MCU高速采样技术实现前端的数据采集,通过串口通信技术,并结合虚拟仪器及Lab VIEW技术开发上位机程序,实现后端的电压数据处理、电渗流流速检测及波形的实时显示。试验及结果分析表明,该检测系统能够较好地满足电渗流平均速度检测的需要。

In accordance with the structural characteristics of micro channel, the transport characteristics of micro fluid, and the driving features of electroosmotic flow（EOF） ; the detection system based on the velocity of electroosmotic flow in micro channel has been designed, and through changing concentration of liquid and intensity of external voltage, the measurement of velocity of EOF is implemented respectively. The design of detection system is based on the monitoring principle of current method, by adopting pre-amplification circuit, filtering circuit, and MSP430 MCU high speed sampling technology simultaneously to implement front-end data acquisition. Through serial port communication technology, and combining virtual instrument and LabVIEW technology, to develop high computer program for implementing back-end voltage data processing, velocity detection of EOF and real time waveform display. The analysis on experimental results shows that this detection system is able well satisfying the requirement of the average velocity detection for EOF.