Silver and Antimicrobial Polymer Nanocomplexes to Enhance Biocidal Effects

Antimicrobial resistance has become a major problem over the years and threatens to remain in the future, at least until a solution is found. Silver nanoparticles (Ag-NPs) and antimicrobial polymers (APs) are known for their antimicrobial properties and can be considered an alternative approach to f...

Full description

Bibliographic Details
Main Authors: Diana Pereira, Susana Ferreira, Gloria Belén Ramírez-Rodríguez, Nuno Alves, Ângela Sousa, Joana F. A. Valente
Format: Article
Language:English
Published: MDPI AG 2024-01-01
Series:International Journal of Molecular Sciences
Subjects:
Online Access:https://www.mdpi.com/1422-0067/25/2/1256
Description
Summary:Antimicrobial resistance has become a major problem over the years and threatens to remain in the future, at least until a solution is found. Silver nanoparticles (Ag-NPs) and antimicrobial polymers (APs) are known for their antimicrobial properties and can be considered an alternative approach to fighting resistant microorganisms. Hence, the main goal of this research is to shed some light on the antimicrobial properties of Ag-NPs and APs (chitosan (CH), poly-L-lysine (PLL), ε-poly-L-lysine (ε-PLL), and dopamine (DA)) when used alone and complexed to explore the potential enhancement of the antimicrobial effect of the combination Ag-NPs + Aps. The resultant nanocomplexes were chemically and morphologically characterized by UV-visible spectra, zeta potential, transmission electron microscopy, and Fourier-transform infrared spectroscopy. Moreover, the Ag-NPs, APs, and Ag-NPs + APs nanocomplexes were tested against Gram-positive <i>Staphylococcus aureus</i> (<i>S. aureus</i>) and the Gram-negative <i>Escherichia coli</i> (<i>E. coli</i>) bacteria, as well as the fungi <i>Candida albicans</i> (<i>C. albicans</i>). Overall, the antimicrobial results showed potentiation of the activity of the nanocomplexes with a focus on <i>C. albicans</i>. For the biofilm eradication ability, Ag-NPs and Ag-NPs + DA were able to significantly remove <i>S. aureus</i> preformed biofilm, and Ag-NPs + CH were able to significantly destroy <i>C. albicans</i> biofilm, with both performing better than Ag-NPs alone. Overall, we have proven the successful conjugation of Ag-NPs and APs, with some of these formulations showing potential to be further investigated for the treatment of microbial infections.
ISSN:1661-6596
1422-0067