Circulating Tumor Cell Separation in a Zigzag Channel Using Dielectrophoresis Based Inertial Microfluidics

Circulating tumor cells (CTCs) are known to be a primary indicator of vital diagnostic and clinical information for early-stage cancer detection. Effective separation of CTCs from blood is crucial for genetic characterization of CTCs, drug development, and improvement of cell cycle-targeted therapies. Many conventional microfluidic platforms isolate CTCs based on their size difference from other blood cells which renders them impractical for sorting overlapping-sized cells. To address this issue, we propose a method using a zigzag channel for continuous, label-free, and high throughput separation of CTCs coupling Dielectrophoresis (DEP) with inertial microfluidics. This hybrid channel exhibits enhanced similar-sized cell separation resolution and single-step retrieval of viable CTCs by combining inertial lift force, DEP force, and alternating curvature-induced Dean force. Through numerical investigation, separation of MDA-231 CTCs from identical-sized WBCs has been achieved at a relatively high Reynolds number of 125. Furthermore, the working parameters such as Reynolds number, voltage, and electrode configuration have been optimized for enhancing the separation efficiency. The proposed design can provide valuable insight into the development of a versatile, efficient, inexpensive, and novel platform with reduced analysis time for cancer diagnosis and prognosis.