Design of a low-voltage dielectrophoresis lab-on-the chip to separate tumor and blood cells

In this paper, we design and propose a compact label-free microfluidic lab-on-a-chip device to separate circulating tumor cells (CTCs) from red blood cells (RBCs) at low voltage to minimize cell damage. With the aim of developing a mm-long device to perform cell separation, we used 3D finite element simulation modeling and investigated separation efficiency for different electrode configurations, electrode shapes, and channel heights. Our results show that configuring the electrodes as two arrays, consisting of only five pairs of top and bottom planar electrodes shifted relative to each other and energized with +/- 6 V at 70 kHz, generates sufficient non-uniform electric fields to separate CTCs and RBCs in a 2 mm long channel. The advantage of the proposed design is the simplicity of the electrode arrangement and that the electrodes do not cover the central part of the channel, thus allowing for brightfield imaging of the channel. In addition, the low voltage needed and the 50 mu m high channel reduce the Joule heating effect and improve the device's separation and throughput efficiency. We suggest that the proposed design would be effective for separating CTCs and RBCs and, thus, used as a device for the early detection of CTCs.