A novel optical‐induced dielectrophoresis (ODEP) method employing a pressure‐driven flow for the continuous separation of microparticles is presented in this study. By applying alternate current electric field on conductive indium tin oxide substrate and projecting the light geometry into the photoconductive layer, an inhomogeneous electric field is locally induced. The particles experience the dielectrophoretic force when passing through the lighting area, where the strongest electrical field gradient exists. By optimizing the structure of the lighting pattern, a stronger nonuniform electric field gradient is generated which predicts the separation of 1 and 3 µm polystyrene particles. Moreover, the effects of key parameters, including the light pattern geometry, applied voltage, and flow rate, were investigated in this study, leading to the successful sorting of 700 nm and 1 µm particles. To further examine the separation sensitivity and practicability of the proposed ODEP microfluidic method, the isolation of two different types of circulating tumor cells from T‐cells and red blood cells are demonstrated, providing a novel method for the manipulation and separation of microparticles and nanoparticles.

中文翻译：

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基于 ODEP 的微流控芯片中微粒操纵和分离的数值研究

本研究提出了一种新型光诱导介电电泳（ODEP）方法，采用压力驱动流来连续分离微粒。通过在导电氧化铟锡基板上施加交流电场并将光几何形状投射到光电导层中，局部感应出不均匀电场。当粒子穿过存在最强电场梯度的照明区域时，会受到介电泳力。通过优化照明图案的结构，产生更强的不均匀电场梯度，预测 1 和 3 µm 聚苯乙烯颗粒的分离。此外，本研究还研究了光图案几何形状、施加电压和流速等关键参数的影响，从而成功分选了 700 nm 和 1 µm 颗粒。为了进一步检验所提出的 ODEP 微流控方法的分离灵敏度和实用性，证明了两种不同类型的循环肿瘤细胞与 T 细胞和红细胞的分离，为微粒和纳米颗粒的操作和分离提供了一种新方法。