Robust Assembly of Cross-Linked Protein Nanofibrils into Hierarchically Structured Microfibers

Abstract

Natural, high-performance fibers generally have hierarchically organized nanosized building blocks. Inspired by this, whey protein nanofibrils (PNFs) are assembled into microfibers, using flow-focusing. By adding genipin as a nontoxic cross-linker to the PNF suspension before spinning, significantly improved mechanical properties of the final fiber are obtained. For curved PNFs, with a low content of cross-linker (2%) the fiber is almost 3 times stronger and 4 times stiffer than the fiber without a cross-linker. At higher content of genipin (10%), the elongation at break increases by a factor of 2 and the energy at break increases by a factor of 5. The cross-linking also enables the spinning of microfibers from long straight PNFs, which has not been achieved before. These microfibers have higher stiffness and strength but lower ductility and toughness than those made from curved PNFs. The fibers spun from the two classes of nanofibrils show clear morphological differences. The study demonstrates the production of protein-based microfibers with mechanical properties similar to natural protein-based fibers and provides insights about the role of the nanostructure in the assembly process.

Keywords

protein nanofibrils; amyloid; hierarchal assembly; cross-linking; flow-focusing

Published in

ACS Nano
2022, volume: 16, number: 8, pages: 12471-12479
Publisher: AMER CHEMICAL SOC

SLU Authors

• Langton, Maud

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Polymer Chemistry
Nano-technology

Publication identifier

• DOI: https://doi.org/10.1021/acsnano.2c03790

Permanent link to this page (URI)

https://res.slu.se/id/publ/118569