Dielectrophoresis is a robust approach for the manipulation and separation of (bio)particles using microfluidic platforms. We developed a dielectrophoretic corral trap in a microfluidic device that utilizes negative dielectrophoresis to capture single spherical polystyrene particles. Circular‐shaped micron‐size traps were employed inside the device and the three‐dimensional trap stiffness (restoring trapping force from equilibrium trapping location) was analyzed using 4.42 μm particles and 1 MHz of an alternating electric field from 6 V_P‐P to 10 V_P‐P. The trap stiffness increased exponentially in the x‐ and y‐direction, and linearly in the z‐direction. Image analysis of the trapped particle movements revealed that the trap stiffness is increased 608.4, 539.3, and 79.7% by increasing the voltage from 6 V_P‐P to 10 V_P‐P in the x‐, y‐, and z‐direction, respectively. The trap stiffness calculated from a finite element simulation of the device confirmed the experimental results. This analysis provides important insights to predict the trapping location, strength of the trapping, and optimum geometry for single particle trapping and its applications such as single‐molecule analysis and drug discovery.

中文翻译：

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介电泳畜栏陷阱三维陷阱刚度的定量分析

介电泳是一种使用微流体平台操作和分离（生物）粒子的稳健方法。我们在利用负介电泳捕获单个球形聚苯乙烯颗粒的微流体装置中开发了介电泳畜栏陷阱。在器件内部采用圆形微米级陷阱，并使用 4.42 μm 粒子和 1 MHz 的交变电场从 6 V _P-P到 10 VP _-P。陷阱刚度在x和y方向呈指数增加，在z方向呈线性增加-方向。被困粒子运动的图像分析表明，通过将x-、y-和z方向的电压从 6 V _P-P增加到 10 V _P-P，陷阱刚度增加了 608.4、539.3 和 79.7% ，分别。从设备的有限元模拟计算的陷阱刚度证实了实验结果。该分析为预测捕获位置、捕获强度和单粒子捕获的最佳几何形状及其应用（如单分子分析和药物发现）提供了重要的见解。