Fig. 2

Characterization of biodegradable porous scaffolds. (A) Representative SEM images of the PLGA, PME, and PMEZ scaffolds (scale bars, up: 200 μm, and bottom: 100 μm). (B) Thermogravimetric analysis (TGA) thermograms of the PLGA, PME, and PMEZ scaffolds. (C) Compressive stress-strain curve and (D) compressive modulus at 5 to 10% of stress-strain curve. (E) Representative confocal images showing distribution of DiO-labeled EV, and Hoechst-labeled IM in the PMEZ scaffolds (Scale bar equals to 20 μm). (F) Nitric oxide release profiles using the electrochemical microsensor. (Values are presented as mean ± SD (n = 3) and statistical significance was obtained with unpaired t tests or one-way analysis of variance (ANOVA) with Tukey’s multiple comparison post-test (*p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001))