Impact of adding glucose-coated water-soluble silver nanoparticles to the silkworm larval diet on silk protein synthesis and related properties

Abstract

Biological modifications of the silk fibroin (silk) material have broad applications in textiles, biomedical materials and other industrial materials. It is economical to incorporate nanoparticles to the biosynthesis of silk fibroin by adding them to silkworm larval diets. This strategy may result in the rapid stable production of modified silk. Glucose-coated silver nanoparticles (AgNPs) were used to improve the AgNPs’ biocompatibility, and the AgNPs were efficiently incorporated into silk by feeding. Larvae fed with AgNPs produced silk with significantly improved antibacterial properties and altered silk secondary structures. Both positive and negative effects on the growth and synthesis of silk proteins were observed after different AgNPs doses. Larvae feeding with low concentration of 0.02% and medium 0.20% AgNPs have greater transfer efficiencies of AgNPs to silk compared with feeding high concentration of 2.00% AgNPs. In addition, the elongation and tensile strength of the produced silk fibers were also significantly increased, with greater mammalian cell compatibility. The appropriate AgNPs concentration in the diet of silkworms can promote the synthesis of silk proteins, enhance their mechanical properties, improve their antibacterial property and inhibit the presence of Gram-negative bacteria.

Graphical Abstract

HIGHLIGHTS

• AgNPs in silkworm diets can be efficiently incorporated into silk.

• Dietary AgNPs can produce antibacterial silk with altered mechanical properties.

• A low dietary AgNPs concentration can enhance silk fibroin synthesis.

Keywords:

• Water-soluble silver nanoparticles (AgNPs)
• silk fibroin
• silk modification
• materials performance
• Bombyx mori

Acknowledgements

The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. We thank Dr. Koh SK for providing water-soluble silver nanoparticles coated with glucose (AgNPs). The manuscript was edited by a native English speaker of International Science Editing Scientific Services.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (Grant No. 31972625 and 31672492), the Natural Science Foundation of Guangxi Province (Grant No. 2016GXNSFBA380156 and 2016GXNSFCA380007), the China Agriculture Research System (CARS) (Grant No. CARS-22-ZJ0104), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant No. KYCX18_2521).