Department of Electrical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand.
Biomedical Engineering Research Center, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand.
Electrophoresis. 2020 Jun;41(10-11):991-1001. doi: 10.1002/elps.201900473. Epub 2020 Feb 28.
This paper presents the application of the discrete dielectrophoretic force to separate polystyrene particles from red blood cells. The separation process employs a simple microfluidic device that is composed of interdigitated electrodes and a microchannel. The discrete dielectrophoretic force is generated by adjusting the duty cycle of the applied voltage. The electrodes make a tilt angle with the microchannel to change the moving direction of the red blood cells. By adjusting the voltage magnitude and duty cycle, we investigate the deflection of red blood cells and the variation of cell velocity along electrode edge under positive dielectrophoresis. The experiments with polystyrene particles show that the enrichment of the particles is greater than 150 times. The maximum separation efficiency is 97% for particle-to-cell number ratio equal to 1:2000 in the sample having high cell concentration. Using the appropriate applied voltage magnitude and duty cycle, the discrete dielectrophoretic force can prevent the clogging of microchannel while successfully separating the particles from the cells with high enrichment and efficiency. The proposed principle can be readily applied to dielectrophoresis-based devices for biomedical sample preparation or diagnosis such as the separation of rare or infected cells from a blood sample.
本文介绍了离散介电泳力在从红细胞中分离聚苯乙烯颗粒中的应用。分离过程采用了一种由交错电极和微通道组成的简单微流控装置。离散介电泳力通过调整施加电压的占空比来产生。电极与微通道成一定角度，以改变红细胞的运动方向。通过调整电压幅度和占空比，我们研究了在正介电泳下红细胞的偏转而细胞速度沿电极边缘的变化。聚苯乙烯颗粒的实验表明，颗粒的富集度大于 150 倍。在细胞浓度较高的样品中，当颗粒与细胞的数量比为 1:2000 时，最大分离效率为 97%。使用适当的施加电压幅度和占空比，离散介电泳力可以防止微通道堵塞，同时成功地将颗粒从高浓度的细胞中分离出来，具有高的富集度和效率。所提出的原理可以很容易地应用于基于介电泳的生物医学样品制备或诊断设备中，例如从血液样本中分离罕见或感染的细胞。
