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Renewable and degradable materials, formed using biopolymers as material precursors, are sought after in pharmaceutical, biomedical, and industrial fields. Silk-based biomaterials, primarily derived from the silk fibroin protein of the Bombyx mori (B. mori) silkworm, have advantageous mechanical properties, biocompatibility, and commercial availability. Recent efforts aim to expand the range of achievable silk-based biomaterial properties via alternative sources of silk proteins with different sequences and structures. These structural distinctions drive differences in physical and chemical properties of silk fibers, primarily due to the varying degree of crystallinity in the polymers. For the development of alternative silk-based materials, silk from Plodia interpunctella (P. interpunctella), a small agricultural pest that infests and damages food products via silk production, is evaluated. Early investigations have highlighted differences between P. interpunctella and B. mori silk fibroin proteins, however P. interpunctella silk still largely lacks characterization and optimization on both the silk fiber and bulk material level. This work evaluates the structural, thermal, mechanical, and cell-material properties of non-degummed and degummed P. interpunctella silk as a raw material for biomaterial fabrication and discusses the benefits and limitations of these proteins as new biopolymers. Observed properties are used to identify links between silk fibroin protein sequence and fiber function in addition to forming hypotheses in how P. interpunctella silk-based biomaterials will perform in comparison to other natural biopolymers. Future work aims to develop methods to process P. interpunctella silk into material formats, utilizing the material characteristics determined here as a baseline for shifts in material performance.
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Polypeptide templating for designer hierarchical materials
Abstract Despite advances in directing the assembly of biomacromolecules into well-defined nanostructures, leveraging pathway complexity of molecular disorder to order transition while bridging materials fabrication from nano- to macroscale remains a challenge. Here, we present templated crystallization of structural proteins to nanofabricate hierarchically structured materials up to centimeter scale, using silk fibroin as an example. The process involves the use of ordered peptide supramolecular assemblies as templates to direct the folding and assembly of silk fibroin into nanofibrillar structures. Silk polymorphs can be engineered by varying the peptide seeds used. Modulation of the relative concentration between silk fibroin and peptide seeds, silk fibroin molecular weight and pH allows control over nanofibrils morphologies and mechanical properties. Finally, facile integration of the bottom-up templated crystallization with emerging top-down techniques enables the generation of macroscopic nanostructured materials with potential applications in information storage/encryption, surface functionalization, and printable three-dimensional constructs of customized architecture and controlled anisotropy.
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- Award ID(s):
- 1752172
- PAR ID:
- 10154274
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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