it has been shown that with increasing incubation time the enzyme cleaved the silk protein at multiple locations along the chains; overall enzymatic degradation was mediated by surface erosion. Additionally, the degradation rate of silk can be altered by the mode of processing the fibroin as well as post-processing treatments, related to the content of β-sheet crystals and degree of organization of the noncrystalline domains. In general, the degradation rate decreases with an increase in overall β-sheet content. In an aside, it has also been shown that the rate of degradation of silk biomaterials directly impacted the metabolism of human mesenchymal stem cells (hMSCs) and consequently altered the rate of osteogenesis. Thus, links between silk fibroin processing, material properties such as degradation rate, and biological activity have been established, and provide a solid basis for utilizing silk as a biomedical material for many applications.