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Abstract Bacterial infections in cystic fibrosis (CF) patients are an emerging health issue and lead to a premature death. CF is a hereditary disease that creates a thick mucus in the lungs that is prone to bacterial biofilm formation, specificallyPseudomonas aeruginosabiofilms. These biofilms are very difficult to treat because many of them have antibiotic resistance that is worsened by the presence of extracellular DNA (eDNA). eDNA helps to stabilize biofilms and can bind antimicrobial compounds to lessen their effects. The metallo‐antimicrobial peptide Gaduscidin‐1 (Gad‐1) eradicates establishedP. aeruginosabiofilms through a combination of modes of action that includes nuclease activity that can cleave eDNA in biofilms. In addition, Gad‐1 exhibits synergistic activity when used with the antibiotics kanamycin and ciprofloxacin, thus making Gad‐1 a new lead compound for the potential treatment of bacterial biofilms in CF patients.
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Conformal Electrodeposition of Antimicrobial Hydrogels Formed by Self‐Assembled Peptide Amphiphiles
Abstract The colonization of biomedical surfaces by bacterial biofilms is concerning because these microorganisms display higher antimicrobial resistance in biofilms than in liquid cultures. Developing antimicrobial coatings that can be easily applied to medically‐relevant complex‐shaped objects, such as implants and surgical instruments, is an important and challenging research direction. This work reports the preparation of antibacterial surfaces via the electrodeposition of a conformal hydrogel of self‐assembling cationic peptide‐amphiphiles (PAs). Hydrogels of three PAs are electrodeposited: C16K2, C16K3, and C18K2, where Cnis an alkyl chain ofnmethylene groups and Kmis an oligopeptide ofmlysines. The processing variables (electrodeposition time, potential, pH, salt concentration, agitation) enable fine control of film thickness, demonstrating the flexibility of the method and allowing to unravel the mechanisms underlying electrodeposition. The electrochemically prepared hydrogels inhibit the growth ofStaphylococcus aureus,Escherichia coli, andPseudomonas aeruginosain agar plates, and prevent the formation of biofilms ofAcinetobacter baumanniiandP. aeruginosaand the formation ofA. baumanniicolonies in solid media. C16K2and C16K3hydrogels outperform the antimicrobial activity of those of C18K2while maintaining good compatibility with human cells.
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- PAR ID:
- 10419241
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 10
- Issue:
- 16
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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