Fig. 3. CTC separation performance of the zigzag channel portion alone.

a Relationship of flow rates and equilibrium positions with respect to the inner channel wall for 10 and 24 μm PS particles. The particle data shown in the figure were acquired from three independent experiments. The flow rate selected for subsequent experiments is shown in the red rectangle. b High-speed microscopy images acquired at the bifurcations indicate the separation of the 10 and 24 μm PS particles (a video is available as SI movie 1). c Distribution of particles at position 4 at four-time points under a flow rate of 1.4 mL/min, demonstrating that the large particles (24 μm; three representative 24 μm PS particles captured in these time-series images are annotated with numbers and shown in the dotted circles.) flow near the center of the channel, while the small particles (10 μm) flow alongside the wall of the channel. d Scatter plots of flow cytometry results showing the proportions of particles (10 and 24 μm) in the initial sample, inner outlet, and outer outlet. The gates were drawn using pure particle samples to discriminate particles of different sizes. e Particle size distribution in each outlet. The data were presented as the mean ± SD (SD, standard deviation, n = 3) values. f High-speed microscopy images acquired at the bifurcations indicate the separation of WBCs and MCF-7 cells (a video is available as SI movie 1). g Scatter plots of flow cytometry results showing the compositions of cells collected from the initial sample, inner outlet, and outer outlet. h Purity of cells in each outlet. The data were presented as the mean ± SD values (n = 6)