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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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Interaction of Blood and Bacteria with Slippery Hydrophilic Surfaces
Abstract Slippery surfaces (i.e., surfaces that display high liquid droplet mobility) are receiving significant attention due to their biofluidic applications. Non‐textured, all‐solid, slippery hydrophilic (SLIC) surfaces are an emerging class of rare and counter‐intuitive surfaces. In this work, the interactions of blood and bacteria with SLIC surfaces are investigated. The SLIC surfaces demonstrate significantly lower platelet and leukocyte adhesion (≈97.2% decrease in surface coverage), and correspondingly low platelet activation, as well as significantly lower bacterial adhesion (≈99.7% decrease in surface coverage of liveEscherichia Coliand ≈99.6% decrease in surface coverage of liveStaphylococcus Aureus) and proliferation compared to untreated silicon substrates, indicating their potential for practical biomedical applications. The study envisions that the SLIC surfaces will pave the path to improved biomedical devices with favorable blood and bacteria interactions.
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- Award ID(s):
- 1947454
- PAR ID:
- 10469376
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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