Inertial focusing of CTCs in a novel spiral microchannel

Circulating Tumor Cells (CTCs), which are rare types of cancer cells, detach from a primary tumor and enter the bloodstream, leading to the formation of metastatic cancer. One of the most effective methods to detect and separate CTCs from the bloodstream is inertial focusing using microfluidic devices. The present work proposed a novel microscale device for continuous flow separation of two types of CTC from blood cells. The MCF-7 (human breast cancer) cells and HeLa (human epithelial cervical cancer) cells, along with blood cells, enter a single-loop spiral microchannel. The cancer cells are separated at the outlet of the channel from each other and the white blood cells (WBCs) and red blood cells (RBCs) due to the inertial force. Different inlet flows of 38-150 ml/h corresponding to the Reynolds numbers of 30-120 are investigated to achieve the maximum separation efficiency of the device. Three-dimensional simulations are performed using the COMSOL Multiphysics 5.5 software and finite element method. It is demonstrated that the separation efficiency reaches 100% over a range of Reynolds numbers from 90 to 110 (throughput range of 113-139 ml/h). (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

A novel microscale device for continuous flow separation of two types of circulating tumor cells from blood cells was proposed in this study. The separation efficiency reached 100% over a range of Reynolds numbers from 90 to 110, achieved through inertial forces.