FIG. 4.

(a)–(c) Simulation results for color-mapped concentration at 2700 s in T-shaped hydrogel devices with different channel lengths. (a) 2.5 cm, (b) 2.75 cm, and (c) 2.95 cm. (d) Simulation result for solute distribution at 2700 s in a microfluidic device with hydrogel-embedded branched channels. The channel length is 2.75 cm. The length of the secondary branches perpendicular to the primary channels is 1.5 mm in all designs. The images reveal sources of inhomogeneities and leakiness during the solute infusion.