Fig. 2. Evaluation of tissue adhesion of hydrogels. (a) Photographs of hydrogel adherence to liver, nerve or chitosan scaffolds. (b) Photographs of hydrogel adherence to porcine skin extended immersion underwater. (c) Photographs of hydrogels for nerve grafting. (d) Bond strengths of hydrogels bound to porcine skin. (e) Bond strengths of hydrogels used for nerve grafting. Data represent the mean ± SD of three independent experiments. *p < 0.05; **p < 0.01; ***p < 0.001 vs. the SA hydrogel.