Figure 4. Integration of drug-delivery channels in tough hydrogel matrix.

a) Schematic illustration of diffusion of drug solution inside hydrogel from the drug-delivery channel. b) Experimental snapshots of drug diffusion in the undeformed hydrogel. c) Experimental snapshots of drug diffusion in the deformed hydrogel. d) Normalized one-dimensional diffusion of mock drug inside undeformed hydrogel channel. e) Normalized one-dimensional diffusion of mock drug inside deformed (λ = 1.6) hydrogel channel. f) Experimental snapshots of the diffusion of multiple mock drugs in a hydrogel matrix under high stretches.