Fig. 3
Experimental setup and side-by-side comparison between theory and experiments. a Schematics of a fixed MFM setup. The MFM is precisely positioned over the surface with a gap controlled by the spacers. b Picture of the experimental setup with holder and MFM clamped atop of an inverted microscope. c–f Side-by-side comparison between analytical and experimental results for various multipolar configurations. The top half of each subfigure is the theoretical concentration profile while the bottom half is a micrograph of a fluorescent dye injected using the MFM (Pe ∼102, Reynolds number ∼10−3). c Microfluidic dipole. d Microfluidic quadrupole. e Polygonal multipole (f) 4-petal axisymmetric “flower” multipole (g) 8-petal axisymmetric “flower” multipole (h) Asymmetric impinging flows of different concentrations. Scale bars = 500 µm
