基于改进等效电容模型的数字微流控液滴定位反馈系统

Digital Microfluidic Droplet Positioning and Feedback System Based on Improved Equivalent Capacitance Model

基于介电润湿(EWOD)效应的数字微流控技术是近十年来出现的一种能够在平面上操控体积为微升、纳升级别液滴的新技术。为了满足对数字微流控中液滴精准驱动与控制的迫切需求,结合现有的液滴定位方法的研究,设计了改进的等效电容模型,该模型方法在无输入参数下实现多液滴的定位。基于该液滴定位模型,提出了驱动参数的反馈优先级调整策略,最终实现了一套具备驱动、定位及反馈一体的数字微流控控制系统。实验结果表明提出的方案有利于提高微液滴的连续输运的成功率,在同样的芯片参数结构下,成功率提高了接近40%,对数字微流控系统进一步的应用研究具有一定指导意义。

Digital microfluidic technology based on electrowetting on dielectric (EWOD)effect is a new technology emerged in recent ten years,which can control droplets with micro-and nano-liter volume on the plane.In order to meet the urgent needs of precise driving and control of droplets in the digital microfluidic,combined with the existing droplet positioning methods,an improved equivalent capacitance model was designed to locate multi-droplets without input parameters. Based on the droplet positioning model,the feedback priority adjustment strategy of driving parameters was proposed.Finally,a digital microfluidic control system with driving,positioning and feedback was obtained.The experimental results show that the proposed scheme is helpful to improve the success rate of the continuous transport of micro droplets,the success rate increases by nearly 40% with the same chip parameter structure.It has certain guiding significance for the further application research of digital microfluidic systems.