title: Potentiated electron transference in α-Ag2WO4 microcrystals with Ag nanofilaments as microbial agent.
abstract: This study is a framework proposal for understanding the antimicrobacterial effect of both α-Ag2WO4 microcrystals (AWO) synthesized using a microwave hydrothermal (MH) method and α-Ag2WO4 microcrystals with Ag metallic nanofilaments (AWO:Ag) obtained by irradiation employing an electron beam to combat against planktonic cells of methicillin-resistant Staphylococcus aureus (MRSA). These samples were characterized by X-ray diffraction (XRD), FT-Raman spectroscopy, ultraviolet visible (UV-vis) measurements, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and high resolution transmission electron microscopy (HRTEM). The results reveal that both AWO and AWO:Ag solutions have bacteriostatic and bactericidal effects, but the irradiated sample is more efficient; i.e., a 4-fold of the MRSA planktonic cells as compared to the nonirradiated sample was observed. In addition, first principles calculations were performed to obtain structural and electronic properties of AWO and metallic Ag, which provides strong quantitative support for an antimicrobacterial mechanism based on the enhancement of electron transfer processes between α-Ag2WO4 and Ag nanoparticles.
authors.affiliation: INCTMN-USP, Universidade de São Paulo, Instituto de Física de São Carlos , 13560-970 São Carlos, SP, Brazil.
authors.forename: Valéria M
authors.initials: VM
authors.lastname: Longo
authors.forename: Camila C
authors.initials: CC
authors.lastname: De Foggi
authors.forename: Mateus M
authors.initials: MM
authors.lastname: Ferrer
authors.forename: Amanda F
authors.initials: AF
authors.lastname: Gouveia
authors.forename: Rafaela S
authors.initials: RS
authors.lastname: André
authors.forename: Waldir
authors.initials: W
authors.lastname: Avansi
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Vergani
authors.forename: Ana L
authors.initials: AL
authors.lastname: Machado
authors.forename: Juan
authors.initials: J
authors.lastname: Andrés
authors.forename: Laécio S
authors.initials: LS
authors.lastname: Cavalcante
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Hernandes
authors.forename: Elson
authors.initials: E
authors.lastname: Longo
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D003198:Computer Simulation; D004583:Electrons; D053768:Metal Nanoparticles / Q000737:chemistry*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000528:radiation effects; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D018030:Silver Compounds / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D018030:Silver Compounds