Figure 1.

(A) Schematic illustration of the preparation procedure of an MR_NCH, and the chemical structures of the components of the pre-gel mixture for MR_NCH. (B) Sol-Gel Transition: Photographs taken before and after the gelation of the PD3 hydrogel, PD3L4 NCH, and PD3L4F2 MR_NCH. (C–E) Cross-sectional SEM images of the freeze-dried PD3 hydrogel, PD3L4 NCH, and PD3L4F2 MR_NCH, respectively and (F–H) the corresponding magnified images of the part marked by the red square. (I) Crosslinking density (v_e) of the PD3 hydrogels, PD3L4 NCHs, and PD3L4F2 MR_NCHs.