Enhanced strength of silk fiber by feeding graphene oxide and its physiology of silkworm

Specific diets are green and efficient method to obtained enhanced robustness silkworm silk, which has been attracted particular research interest. Graphene oxide is widely used for biomedicine and reinforcement. Thus, in this work, we reported enhanced mechanically silk directly collected by feeding Bombyx mori silkworms with graphene oxide and its physiology of silkworm was explored. These results suggested that feeding graphene oxide can promote silkworm growth and development slightly. And cocoon weight was also increased by feeding graphene oxide. Furthermore, it was found that the activity of alkaline phosphatase related to absorption and metabolism, the content of reduced glutathione related to antioxidant capacity were increased with graphene oxide incorporation. The stability of silk protein in silk glands was also changed with graphene oxide incorporation. And the content of amino acids in the hemolymph and silk were affected. In addition, it suggested that feeding graphene oxide has a great influence on the secondary structure of silk, resulting in the reduction of β-sheet structure, crystallinity, crystal size, and the increase of orientation, polar amino acid content, intermolecular force. Thus, mechanically processed silk was obtained, demonstrating significant potential for utilization in the fields of reinforced composites and biomedicine.