Figure 4.

A. Mechanism of deterministic lateral displacement. Streamlines 1, 2, and 3 do not mix. If a cell or particle is large enough to be located primarily in streamline 3, as shown in the diagram, it will flow to the right of the pillars. Reprinted with permission from (Huang, Cox, Austin, & Sturm, 2004) . B. Free-body diagram of forces experienced by cells or particles during inertial focusing that pushes them toward equilibrium positions in a channel based on size. Reprinted with permission from (Zhou & Papautsky, 2013). C. Weir-type filter used to capture cells below a size/deformability threshold; once cells are trapped by centrifugal forces and negative pressure (i), back-flow is used to recover the cells from the device (ii). Adapted with permission from (Yeo et al., 2016). D. Trace of path of cells in Vortex device. At a constant, high flow rate, larger cells are trapped in large sections of the channel in microvortices, while smaller cells pass through to the outlet. When the flow rate is reduced, larger cells exit the vortices and are recovered at the outlet. Reprinted with permission from (Che et al., 2016).