Figure 16.
Sheath microfluidic system with different magnet structures. A, A stack of four permanent magnets was embedded into a PDMS chip with their magnetization direction vertical to the channel during curing. 142 B, The particle flow is aligned with the wall near a nickel microstructure, where the maximum magnetic field gradient is achieved. When a magnetic field perpendicular to the direction of flow is applied by a permanent magnet adjacent to the nickel microstructure, cells in a paramagnetic solution are deflected laterally because of magnetic repulsion force. 119 C, Mechanism underlying the isolation of particles with different sizes based on water sheath flow under a local magnetic force generated by microfabricated sawtooth‐shaped magnets 143