Isolation of Nanofibrils from Animal Silks

The presence of well-organized nanofibrils in animal silks is considered to provide them excellent mechanical and biochemical properties. To direct utilize these unique natural nanomaterials, a variety of physical and/or chemical processes have been developed for directly isolating silk nanofibrils from animal silks. The yield and processability of these techniques as well as the morphologies of resultant silk nanofibrils have apparent differences but also have their own merits. In this chapter, I presented the protocols for isolation silk nanofibrils, including a physical approach of sonication, a chemical approach of salt-formic acid dissolution, as well as three combination approaches, hexafluoroisopropanol liquid exfoliation, urea-guanidine hydrochloride dissolution, and sodium hypochlorite partial dissolution.