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Abstract Bacterial biofilms on the surfaces of indwelling biomedical devices can cause long‐term infection and patient morbidity and mortality. Wrinkled surface topographies have previously demonstrated promising antifouling properties. Here we report a bioinspired strategy in which the actuation of silk fibroin produces tunable, wrinkled surface topographies on 2D shape memory polymer (SMP) substrates and investigate the influence of these topographies on biofilm formation. To mimic biofilm‐associated infections related to the geometries of indwelling medical devices, silk wrinkles are produced on complex, 3D SMP architectures, and biofilm formation is evaluated. Using common biofilm‐causing agents, smaller silk wrinkle wavelengths and amplitudes are found to significantly reduce biofilm formation, resulting in primarily isolated, single‐cell bacteria on the 2D wrinkled surfaces. These single‐cell bacteria are nearly completely eradicated by treatment with antibiotics, which are ineffective against control surfaces. Antibiotics are also physically incorporated into the 2D wrinkled surfaces, which resulted in a further significant reduction in bacterial adhesion. Lastly, silk wrinkled topographies are successfully applied on 3D architectures, and the wrinkled surfaces display a significant reduction in biofilm coverage compared to controls. The findings demonstrate the potential for biopolymer wrinkles on biomaterials to be used as antifouling surfaces for biofilm prevention.
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This content will become publicly available on July 3, 2025
Dry and wet wrinkling of a silk fibroin biopolymer by a shape-memory material with insight into mechanical effects on secondary structures in the silk network
Upon contraction, the silk fibroin (SF)-shape-memory polymer (SMP) bilayer produces wrinkles. Results support the potential use of biopolymer wrinkles on active materials in biomedical applications, such as cell mechanobiology or tissue engineering.
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- PAR ID:
- 10540543
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Journal of Materials Chemistry B
- Volume:
- 12
- Issue:
- 26
- ISSN:
- 2050-750X
- Page Range / eLocation ID:
- 6351 to 6370
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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