“…Besides the inherent virtues of silk fibroin, such as biocompatibility, a green formation process, and tunable biodegradability, another feature is its diversity of conformations, hierarchical microstructures and various material states, endowing the possibility of designing biomaterials with selective and useful performance (Gorenkova et al, ; Hu et al, ; Kumar, Nandi, Kaplan, & Mandal, ; Qi et al, ; Rockwood et al, ). However, it is difficult to fabricate soft, insoluble RSF scaffolds in the absence of chemical crosslink reagent such as glutaraldehyde or horseradish peroxide, since enough beta‐sheet structure is considered a prerequisite for water‐insolubility, but in turn results in a higher stiffness for the material (Cao et al, ; Kim, Park, Kim, Wada, & Kaplan, ; Zheng et al, ).…”