Effect of Degumming Methods on the Degradation Behavior of Silk Fibroin Biomaterials

Degradation behavior is a key consideration in the field of silk fibroin (SF) biomaterials. Degumming to remove sericin is a prerequisite for SF purification; however, the impact of degumming on the degradation behavior of SF biomaterials has not been established. In this study, two different degumming systems, Na2CO3 and NaHCO3, were used. Na2CO3 exhibited higher degumming efficiency but caused greater degradation of the fibroin. The results demonstrated that NaHCO3 degumming could afford regenerated SF with higher molecular weight, resulting in SF films with higher mechanical strengths. The enzymatic degradation behaviors indicated that the SF films prepared by the Na2CO3 degumming process showed faster degradation, revealing that the choice of degumming method has a substantial impact on the biodegradation of SF-based materials. The results showed that manipulating the degumming conditions can be used to tune the molecular weight of the SF, in turn providing control over the degradation rate of SF biomaterials.