摘要
针对目前数字微流控芯片驱动电压比较高的问题,本文对比传统的驱动电极结构,研制了一种可以降低驱动电压的半月形驱动电极数字微流控芯片。首先,基于介电湿润原理,分析微液滴所受介电湿润力和微液滴接触圆上有效三相接触线所对应弦长的关系。接着,对比分析了传统的方形、叉齿形驱动电极与提出的半月形驱动电极上液滴有效三相接触线所形成的弦长大小;分析得出3种驱动电极结构中半月形驱动电极所形成的有效弦长最大,从而表明半月形驱动电极的数字微流控芯片上介电驱动力最大。最后,利用设计制作的3种驱动电极介电湿润芯片分别实验验证驱动液滴的效果。结果表明,所研制的半月形驱动电极数字微流控芯片的最小驱动电压分别比方形和叉齿形驱动电极芯片降低了约37%和67%。另外,当有效驱动电压为60V时,半月形驱动电极芯片上2μL去离子水微液滴的速度约为10cm/s,分别是方形与叉齿形驱动电极芯片上液滴速度的3倍和2倍。得到的实验数据证明了半月形驱动电极数字微流控芯片实现了降低芯片驱动电压的目的。
According to the high driving potential of existing digital microfluidic devices,a novel crescent electrode was designed to reduce the driving potential based on traditional electrode structure.First,based upon the theory of electrowetting-on-dielectric （EWOD）,the relation between the driving force exerted on a micro-droplet and the chord length of an effective Triple Contact Line （TCL）of the contact circle of the micro-droplet was analyzed.Then,the chord lengths of the effective TCLs from a square electrode,a jagged electrode and the crescent electrode were analyzed.It shows that the chord length of TCL from the crescent electrode is the maximal,so the driving force exerted on the droplet in the digital microfluicic device with the crescent electrode was the maximal.Finally,the droplet driving effect was tested via three kinds of electrode devices.The experimental results show that the minimum driving potential on the device with the crescent electrode can reduce approximately 37％ and 67％ as compared with those of the square and jagged electrode devices.Furthermore,when the driving potential is 60 VRMS,a 2μL droplet can be driven at a velocity of 10 cm/s,which is triple and double the velocity of the same droplet on the square and jagged electrode devices.The obtained experimental results validate the feasibility of reducing the driving potential of digital microfluidic device with the crescent electrode.
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2013年第10期2557-2565,共9页
Optics and Precision Engineering
基金
国家自然科学基金资助项目(No.51275327)
关键词
数字微流控芯片
介电湿润
微液滴
半月形电极
驱动电压
digital microfluidic device
electrowetting-on-dielectric
micro-droplet
crescent electrode
driving potential
