Circulating tumour cells isolation in Asymmetrical meandering microchannel

Abstract

A microfluidic method is presented in the current work which allows full separation of circulating tumour cells (CTCs) from the blood biopsy of cancer patients. The method is based on using a microchannel with two separation zones. The first zone is meandering and equipped with seven identical electrodes. These electrodes generate dielectrophoretic forces that affect mostly the platelets and force them to separate first in this zone. This leaves only the target cells (CTCs) with RBCs and WBCs to flow through an expanded, curved section of the channel (second zone). This unique configuration allows generating intense hydrodynamic forces that can isolate CTCs completely. A numerical model is used to give insight into the cells separation and examine the performance of the proposed channel at different operating conditions. The computational results indicated that all CTCs can be separated when operating at a blood volume flow rate ranging from 10 to 20 µl/h. The two main electrical parameters (electrode voltage and AC current frequency) are also examined. The results showed that the voltage between 15 and 30 V and frequency between 20 and 70 kHz are the best ranges to isolate pure CTCs completely without including any blood cells (i.e. 100 % both separation efficiency and purity). Further, CTCs size is changed from 12 to 26 µm to mimic the effect of different CTC types and the results demonstrate clearly that with a single design various types of cancerous cells can be handled effectively.