Enhanced Particle Trap: Design and Simulation of Pillar-Based Contactless Dielectrophoresis Microfluidic Devices.

Contactless and conventional dielectrophoresis (DEP) microfluidic devices are extensively utilized in lab-on-a-chip applications, particularly for cell isolation and analysis. Nonetheless, these devices typically operate at low throughput and require high applied voltages, posing limitations for microfluidic cell isolation and separation. Addressing these challenges, this study explores the utilization of diverse micro-pillar geometries within the microfluidic device to augment THP-1 cell trapping efficiency numerically using FEM modeling. Furthermore, the simulations examine the influence of pillar gap and quantity on cell trapping efficiency in a contactless DEP device. Notably, elliptical pillars demonstrate superior cell trapping efficiency at elevated flow rates compared to alternative configurations, making the microchip more amenable for high-throughput cell separation, trapping, and isolation applications. Remarkably, employing elliptical pillars in a contactless DEP microfluidic chip yields nearly 100% cell trapping efficiency at higher flow rates. Ellipse configuration showed 122% higher cell trap efficiency at the maximum flowrate compare to the previous study with circular configuration. Additionally, it is observed that reducing the gap between pillars correlates with enhanced cell trapping efficiency. Simulation outcomes indicate that employing two rows of elliptical pillars with a 40-µm gap achieves optimal performance. The findings of this investigation underscore the importance of pillars in contactless DEP devices and provide valuable insights for future designs of such microfluidic devices.