FIG. 1.

Effects of glycol chitosan and uniaxial mechanical stimulation on the mechanical and adhesive properties of hydrogels. Cell-free, cell-laden, free-swelling, and loaded GelMA (15%; w/v) and GelMA-GC (GelMA 15% and GC 1%, w/v) hydrogels cross-linked with Ru/SPS photo-initiators at 405 nm into the central defect of bovine articular cartilage on day 1 and 28. Elastic modulus calculated from the micro-indentation test by cellscale micro-tester at 37 °C in PBS (pH = 7.4) bath (a) cell-free and (b) cell-laden hydrogels. Shear strength of (c) cell-free and (d) cell-laden hydrogels measured after push-out test using an Instron 5567 tester with a nonporous indenter and a 5 N load cell at 37 °C in PBS (pH = 7.4) bath. Shear modulus of (e) cell-free and (f) cell-laden hydrogels measured after push-out test using an Instron 5567 tester with a nonporous indenter and a 5 N load cell at 37 °C in PBS (pH = 7.4) bath. Groups that do not share a common Roman numeral are statistically different (p < 0.05). GelMA (15%, w/v) hydrogels were considered as control. Sample size n = 4 per group; error bars: Mean + SD.