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N-acetylcysteine-functionalized coating avoids bacterial adhesion and biofilm formation.

ABSTRACT: N-acetyl cysteine (NAC) is an FDA-approved drug clinically applied on a broad range of pathologies. Further research has been conducted with this drug to benefit from its antimicrobial activity potential. However, NAC has a very short half-life and therefore strategies that accomplish high local concentrations would be beneficial. In this study, covalent immobilization of NAC was performed, in order to obtain long-lasting high local concentration of the drug onto a chitosan(Ch)-derived implant-related coating. For the development of NAC-functionalized Ch films, water-based carbodiimide chemistry was applied to avoid the use of toxic organic solvents. Here we report the optimization steps performed to immobilize NAC onto the surface of pre-prepared Ch coatings, to ensure full exposure of NAC. Surface characterization using ellipsometry, water contact angle measurements and X-ray photoelectron spectroscopy (XPS), demonstrated the success of NAC immobilization at 4?mg/mL. Quartz crystal microbalance with dissipation (QCM-D) demonstrated that surface immobilized NAC decreases protein adsorption to Ch coatings. Biological studies confirmed that immobilized NAC4 avoids methicillin-resistant Staphylococcus aureus adhesion to Ch coating, impairing biofilm formation, without inducing cytotoxic effects. This is particularly interesting towards further developments as a prevention coating.

SUBMITTER: Costa F

PROVIDER: S-EPMC5727138 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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N-acetylcysteine-functionalized coating avoids bacterial adhesion and biofilm formation.

Costa Fabíola F Sousa Daniela M DM Parreira Paula P Lamghari Meriem M Gomes Paula P Martins M Cristina L MCL

Scientific reports 20171212 1

N-acetyl cysteine (NAC) is an FDA-approved drug clinically applied on a broad range of pathologies. Further research has been conducted with this drug to benefit from its antimicrobial activity potential. However, NAC has a very short half-life and therefore strategies that accomplish high local concentrations would be beneficial. In this study, covalent immobilization of NAC was performed, in order to obtain long-lasting high local concentration of the drug onto a chitosan(Ch)-derived implant-r ...[more]

PMID: 29234086

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N-acetylcysteine-functionalized coating avoids bacterial adhesion and biofilm formation.

Publications

N-acetylcysteine-functionalized coating avoids bacterial adhesion and biofilm formation.

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