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The field of soft wearable bioelectronics requires materials that are flexible, stretchable, biocompatible, and capable of being used over long durations. Although polydimethylsiloxane (PDMS) is one of the most commonly used substrates for these devices due to its biomimetic properties compared to biological tissues, its intrinsic hydrophobicity causes it to underperform in biological environments. In this work, a hydrophilic, stretchable PDMS electrospun fibrous mat is developed to overcome this limitation by incorporating the amphiphilic polymer polyethylene glycol block copolymer (PEG‐BCP) into the porous PDMS matrix. The nonwoven hydrophilic silicone mat shows apparent improvement in stable hydrophilicity, indicated by a significant decrease in water contact angle (from 125° to 51°) for 7 days, along with improved cellular adhesion and enhanced breathability. The PDMS‐PEG fibers show higher cell proliferation than unmodified PDMS fibers, suggesting potential for long‐term biological applications. The fibrous mat also maintains its structural integrity under mechanical stress, demonstrated by a stretchability of up to 308.8% strain with reduced adhesion forces. This novel material surpasses previous PDMS fibrous substrates and enables electroless gold plating, providing a promising future for wearable fibrous electronics and biomedical devices featuring hydrophilic, stretchable, conductive, and biointegrated materials.
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This content will become publicly available on April 24, 2026
Antifouling Activity of Bottlebrush Network Hydrogels
Mitigating the attachment of microorganisms to polymer biomaterials is critical for preventing hospital-acquired infections. Two chemical strategies to mitigate fouling include fabricating fouling-resistant surfaces, which typically present hydrophilic polymers, such as polyethylene glycol (PEG), or creating fouling-release surfaces, which are generally hydrophobic featuring polydimethylsiloxane (PDMS). Despite the demonstrated promise of employing PEG or PDMS, amphiphilic PEG/PDMS copolymer materials remain understudied. Here, for the first time, we investigated if phase-separated amphiphilic copolymers confounded microbial adhesion. We used bottlebrush amphiphilic PEG/PDMS co-networks and homopolymer networks to study bacterial adhesion across a library of gels (ϕPEG = 0.00, 0.21, 0.40, 0.55, 0.80, and 1.00). Hydrated atomic force microscopy measurements revealed that most of the gels had low surface roughness, less than 5 nm, and an elastic modulus of ∼80 kPa. Interestingly, the surface roughness and elastic modulus of the ϕPEG = 0.40 gel were twice as high as those of the other gels due to the presence of crystalline domains, as confirmed using polarized optical microscopy on the hydrated gel. The interactions of these six well-characterized gels with bacteria were determined using Escherichia coli K12 MG1655 and Staphylococcus aureus SH1000. The attachment of both microbes decreased by at least 60% on all polymer gels versus the glass controls. S. aureus adhesion peaked on the ϕPEG = 0.40, likely due to its increased elastic modulus, consistent with previous literature demonstrating that modulus impacts microbial adhesion. These findings suggest that hydrophilic, hydrophobic, and amphiphilic biomaterials effectively resist the early attachment of Gram-negative and Gram-positive microorganisms, providing guidance for the design of next-generation antifouling surfaces.
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- Award ID(s):
- 1904901
- PAR ID:
- 10585649
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- ACS Applied Bio Materials
- ISSN:
- 2576-6422
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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