Negative Dielectrophoretic Force based Cell Sorter with Simplified Structure for High Reliability

In this article, a cell sorter with a simplified structure is presented. This sorter harnesses negative dielectrophoretic (n-DEP) force and gravity. In order to enhance the throughput and recovery rate, a meso-sized (15 mmx40 mmx200 mu m) channel assembled with two transparent plates and two side walls is employed. Since a complex structure would degrade the cell sorter's performance due to the leaking phenomenon as well as cell adhesion, the structure of the proposed sorter is simplified by minimizing the number of components. In addition, microelectrode arrays are designed with five continuous microelectrode pairs. This configuration utilizes continuous separation at each electrode pair, thereby enabling greater separation efficiency. As the drag force, gravity and n-DEP force are the principal parameters of the cell sorter, they are evaluated around the DEP barrier. Subsequently, based on the numerical simulation and theoretical results, separation conditions are experimentally investigated. Consequently, 7 Vp-p at 10 kHz is selected as the input condition. In order to evaluate the cell sorter, K562 cells - cancer cells found in bone marrow - are selected for use as target cells. In the experiments, a separation efficiency of 94.74 +/- 0.77%, a throughput of 17,000 cells/min and a recovery rate of 49.42% are achieved.