González Ortiz, BlancaColilla Nieto, MontserratDíez, JaimePedraza, DanielGuembe, MartaIzquierdo Barba, IsabelVallet Regí, María Dulce Nombre2023-06-172023-06-172018-03-011742-706110.1016/j.actbio.2017.12.041https://hdl.handle.net/20.500.14352/11951RESEARCHER ID K-4773-2015 (Blanca González Ortiz) ORCID 0000-0002-0493-6071 (Blanca González Ortiz) RESEARCHER ID N-4628-2014 (Montse Colilla Nieto) ORCID 0000-0003-1961-4160 (Montse Colilla Nieto) RESEARCHER ID M-9921-2014 (Isabel Izquierdo Barba) ORCID 0000-0002-4139-4646 (Isabel Izquierdo Barba) RESEARCHER ID M-3378-2014 (María Vallet Regí) ORCID 0000-0002-6104-4889 (María Vallet Regí)This work aims to provide an effective and novel solution for the treatment of infection by using nanovehicles loaded with antibiotics capable of penetrating the bacterial wall, thus increasing the antimicrobial effectiveness. These nanosystems, named "nanoantibiotics", are composed of mesoporous silica nanoparticles (MSNs), which act as nanocarriers of an antimicrobial agent (levofloxacin, LEVO) localized inside the mesopores. To provide the nanosystem of bacterial membrane interaction capability, a polycationic dendrimer, concretely the poly(propyleneimine) dendrimer of third generation (G3), was covalently grafted to the external surface of the LEVOloaded MSNs. After physicochemical characterization of this nanoantibiotic, the release kinetics of LEVO and the antimicrobial efficacy of each released dosage were evaluated. Besides, internalization studies of the MSNs functionalized with the G3 dendrimer were carried out, showing a high penetrability throughout Gram-negative bacterial membranes. This work evidences that the synergistic combination of polycationic dendrimers as bacterial membrane permeabilization agents with LEVO-loaded MSNs triggers an efficient antimicrobial effect on Gram-negative bacterial biofilm. These positive results open up very promising expectations for their potential application in new infection therapies.engjournal articlehttps://www.elsevier.com/http://www.ucm.es/valletregigroupopen access546615.46616.9Mesoporous Silica NanoparticlesPolycationic dendrimersBacterial internalizationAntimicrobial deliveryBiofilmInfection treatmentMaterialesEnfermedades infecciosasQuímica inorgánica (Farmacia)3312 Tecnología de Materiales3205.05 Enfermedades Infecciosas