FIG. 7.

(a) Z-stack projection of videomicroscopic images representing superparamagnetic particles flowing at the vicinity of an i-PDMS microstructure in presence of an external magnetic field. Y-positions of the beads are measured at two different locations 500 μm, respectively, upstream and downstream of the center of the structure, allowing calculating the deviation of the bead ΔY = Y₁ − Y₀. (b) Evolution of the deviation ΔY of the beads versus their position upstream of the microstructure, with and without external magnetic field. The beads are flowing at 200 μl/h. The curves are guide for the eyes. We defined W_influence (light grey) and W_capture (dark grey) as the portion of the channel width where the beads are deviated and captured, respectively. (c) Evolution of W_influence and W_capture as a function of the flow rate Q. The curves are guides for the eyes.