Figure 5 |. High molecular weight alginates facilitate stronger adhesion.

(a-c) The effect of alginate molecular weight on hydrogel toughness, modulus, and the adhesion energy was evaluated using both ultrapure (UP) and non-ultrapure (Non-UP) polymers. For the high MW alginates A and C were used, while alginates C and F were used as the low MW alginates. Data shown as mean ± s.d., as evaluated by a one-way ANOVA with post hoc t-tests with Bonferroni corrections (n=4–6 samples/group). (d) The adhesion energy was strongly correlated with alginate molecular weight (R² = 0.7166, P<0.001). Adhesion tests on panels a-c were performed using tough gels with alginates A or C as the UP materials, and alginates E and F as the Non-UP. All tests were performed using chitosan A. See tables S1 and S2 for additional specifications.