CONICET | Buscador de Institutos y Recursos Humanos

Silver nanoparticles (AgNPs) constitute a very promising approach for overcoming the emergence of antibiotic resistancebacteria. Although their mode of action could be related with membrane damage, the AgNPs-lipid membraneinteraction is still unclear. In this sense, the present work investigated the interaction of model lipid membraneswith AgNPs coated with different capping agents such as citrate (C-AgNPs) and phytomolecules (G-Ag-NPs) obtained via a green synthesis. The AgNPs-membrane interactions were evaluated studying i) the surfacepressure changes on both zwitterionic (DMPC) and negatively charged (DMPC:DMPG) lipid monolayers, ii) thezeta potential and DLS of DMPC:DMPG liposomes and iii) Zeta potential on Escherichia coli membranes, incubatedwith this nanomaterials. The results showed that both negatively charged-AgNPs can interact with these lipidmonolayers inducing an increase in the surface pressure but G-AgNPs presented a significantly higher affinitytoward both monolayers in comparison with C-AgNPs. Zeta potential data confirmed again the interaction eventshowing that both DMPC:DMPG liposomes and E. coli bacteria became more negative with the addition of G-Ag-NPs. This increased net negative charge of the liposomes and E. coli allows to indicate an interfacial interactionwhere the green nanometal should keep adsorbed to the membrane via the insertion of aromatic/hydrophobicmoieties of capping agents on the surface of AgNPs into the lipid bilayer. Summarizing, the AgNPs-membrane interactionshould be an essential step in the antibacterial activity either because the membrane is the main targetor by increasing the local concentration of silver from G-AgNPs accumulation what could cause the bactericidaleffect

enviar mensaje