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Abstract Each year, thousands of patients die from antimicrobial‐resistant bacterial infections that fail to respond to conventional antibiotic treatment. Antimicrobial polymers are a promising new method of combating antibiotic‐resistant bacterial infections. We have previously reported the synthesis of a series of narrow‐spectrum peptidomimetic antimicrobial polyurethanes that are effective against Gram‐negative bacteria, such asEscherichia coli; however, these polymers are not effective against Gram‐positive bacteria, such asStaphylococcus aureus. With the aim of understanding the correlation between chemical structure and antibacterial activity, we have subsequently developed three structural variants of these antimicrobial polyurethanes using post‐polymerization modification with decanoic acid and oleic acid. Our results show that such modifications converted the narrow‐spectrum antibacterial activity of these polymers into broad‐spectrum activity against Gram‐positive species such asS. aureus, however, also increasing their toxicity to mammalian cells. Mechanistic studies of bacterial membrane disruption illustrate the differences in antibacterial action between the various polymers. The results demonstrate the challenge of balancing antimicrobial activity and mammalian cell compatibility in the design of antimicrobial polymer compositions. © 2019 Society of Chemical Industry
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Dual‐Functional Dextran‐PEG Hydrogel as an Antimicrobial Biomedical Material
Abstract Microbial infections continually present a major worldwide public healthcare threat, particularly in instances of impaired wound healing and biomedical implant fouling. The development of new materials with the desired antimicrobial property to avoid and treat wound infection is urgently needed in wound care management. This study reports a novel dual‐functional biodegradable dextran‐poly(ethylene glycol) (PEG) hydrogel covalently conjugated with antibacterial Polymyxin B and Vancomycin (Vanco). The hydrogel is designed as a specialized wound dressing that eradicates existing bacteria and inhibits further bacteria growth, while, ameliorating the side effects of antibiotics and accelerating tissue repair and regeneration. The hydrogel exhibits potent antibacterial activities against both gram‐negative bacteriaEscherichia coli(E. coli) and gram‐positive bacteriaStaphylococcus aureus(S. aureus) with no observable toxicity to mouse fibroblast cell line NIH 3T3. These results demonstrate the immense potential of dextran‐PEG hydrogel as a wound dressing healthcare material in efficiently controlling bacteria growth in complex biological systems.
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- Award ID(s):
- 1723667
- PAR ID:
- 10047346
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Bioscience
- Volume:
- 18
- Issue:
- 2
- ISSN:
- 1616-5187
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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