Figure 2.

Secondary structure and microscopic morphology of the silk nanofiber hydrogels with mechanical gradient cues. (A) XRD and (B) FTIR spectra of different areas of the hydrogels with various mechanical properties; (C) AFM images of different area of the hydrogels with various mechanical cues. Higher amount of BSNF appeared at the sites with stiffer mechanical properties; (D) SEM images of different area of the hydrogels with various mechanical cues. The images exhibited better anisotropic morphologies at sites with stiffer mechanical properties. White arrows indicated the aligned structures