Fig. 2

a–e XPS analyses of GO powder, the uncross-linked 0%, 0%, uncross-linked 0.1%, and 0.1% groups. Scaffolds containing 0.1% GO before and after cross-linking are labeled “Uncross-linked 0.1%” and “0.1%,” respectively. Scaffolds without GO before and after cross-linking are labeled “Uncross-linked 0%” and “0%,” respectively. f FTIR spectra of the scaffolds. g Compressive elastic modulus of each scaffold. h Degradation of each scaffold. Statistically significant differences are indicated with *p < 0.05 and **p < 0.01 versus the 0% group