Viscoelastic properties of DN hydrogels are tuned through the amount of independent networks. Rheological measurements (1.0 Hz, 0.5% strain) of (A) storage modulus (G′ and (B) tan(δ) for DN hydrogels with PEG-fibrinogen (8.5 mg mL−1) and varied GH (0, 3, 5%) and PEG-DA (1, 2, 3%) concentrations (conc., n = 3 replicates per group, mean ± SD, **p ≤ 0.01 by one-way ANOVA with Bonferroni post hoc). (C) Tan(δ) of DN hydrogels with various molar ratios of GH/PEG-DA (n = 3 replicates per group, mean ± SD). Colored symbols represent examples of DN hydrogels (PEG-fibrinogen (8.5 mg mL−1) plus 2% PEG-DA) with varied GH concentrations.