Figure 3.
Fluorescence assays performed to investigate the diffusion process of two side streams composed of 10 μM fluorescein through a 3D-printed concentration-controlled microfluidic device. Chips with four flow rate ratios (Rf) of 0.5, 1, 2, 4 were explored. Fluorescent microscopy images were taken at distances of 0, 10, 50, 70, 100 mm away from the inlets of channels. The yellow lines indicate fluorescence intensity profiles at the corresponding locations. X and Y represent the relative channel width and fluorescence intensity, respectively. Scale bar was 2 mm.