Li Haibo, Bashir Rashid
School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907-1285, USA.
Biomed Microdevices. 2004 Dec;6(4):289-95. doi: 10.1023/B:BMMD.0000048561.26086.1a.
Microfabricated interdigitated electrode array is a convenient form of electrode geometry for dielectrophoretic trapping of biological particles within micro-fluidic biochips. We have previously reported experimental results and finite element modeling of the holding forces for both positive and negative dielectrophoretic traps on microfabricated interdigitated electrodes within a microfluidic biochip fabricated in silicon with a 12 microm deep chamber and anodic-bonded glass cover. Based on these prior studies, we present in this paper a dynamic study to investigate the stopping capability of dielectrophoretic devices with limited electrode teeth. Simulation results on the issues of design and optimization of the dielectrophoretic devices are also presented and discussed in detail. Simulation results show that the maximum particle stopping distance in a specific device is very sensitive to the chamber height due to the near-electrode nature of DEP force. The relationship between maximum stopping distance and the applied voltage is presented, and the electrode spacing is found to be important in designing the electrode geometry. The spacing should be no less than the chamber height in order to efficiently capture the particles in a relatively short range at a given applied voltage and flow rate.
微纳加工的叉指电极阵列是一种方便的电极几何形状，可用于在微流控生物芯片中通过介电泳捕获生物颗粒。我们之前已经报道了在一个由硅制成的、具有12微米深腔室和阳极键合玻璃盖的微流控生物芯片中，微纳加工叉指电极上正负介电泳阱的保持力的实验结果和有限元建模。基于这些先前的研究，我们在本文中进行了一项动态研究，以研究电极齿有限的介电泳装置的捕获能力。还详细介绍并讨论了介电泳装置设计和优化问题的模拟结果。模拟结果表明，由于介电泳力的近电极性质，特定装置中的最大颗粒捕获距离对腔室高度非常敏感。给出了最大捕获距离与施加电压之间的关系，并且发现电极间距在设计电极几何形状时很重要。为了在给定的施加电压和流速下在相对较短的范围内有效捕获颗粒，间距应不小于腔室高度。
