Optimal Parameter Configuration of a Microfluidic Chip for High-Throughput, Label-Free Circulating Tumor Cell Separation and Enrichment Based on Inertial Focusing.

To simply, quickly, and efficiently separate circulating tumor cells from blood has always been an enormous challenge. Leveraging the principle of inertial focusing, we here designed a simply structured microfluidic chip that maintained excellent CTC separation efficiency with high robustness and low velocity sensitivity across a broad velocity range. The parameter configuration of the chip was systematically examined, especially the most influential parameters such as the arc radius and arc angle. With optimal parameters, the designed chip achieved an outstanding particle separation efficiency of 99.8% and, more importantly, enabled the efficient separation and enrichment of CTCs in blood samples. This design can be readily integrated with other functional modules for further sample processing, serving as a promising tool for cancer diagnosis and therapeutics.