Figure 1.

Final mechanical properties are dictated by gel formulation. (a) The swollen hydrogel shear elastic moduli are easily tuned by changing the molecular weight of the PEG cross-linker (◻ = 10 000 g/mol, ▲=15 000 g/mol, ○ = 20 000 g/mol). Alternatively, small stoichiometric imbalances between the gel-forming azide and cyclooctyne reactive groups also give rise to materials with a wide range of moduli. (b) Changes in gel formulation result in hydrogels with different equilibrium swelling ratios (in PBS). (c) The swelling ratio (▲) and equilibrium shear moduli (○) data collapse onto a single curve for all conditions when normalized to cross-linking density. Data reported as mean ± std.