title: Plasma deposition of silver nanoparticles on ultrafiltration membranes: antibacterial and anti-biofouling properties.
abstract: A novel and versatile plasma reactor was used to modify Polyethersulphone commercial membranes. The equipment was applied to: i) functionalize the membranes with low-temperature plasmas, ii) deposit a film of poly(methyl methacrylate) (PMMA) by Plasma Enhanced Chemical Vapor Deposition (PECVD) and, iii) deposit silver nanoparticles (SNP) by Gas Flow Sputtering. Each modification process was performed in the same reactor consecutively, without exposure of the membranes to atmospheric air. Scanning electron microscopy and transmission electron microscopy were used to characterize the particles and modified membranes. SNP are evenly distributed on the membrane surface. Particle fixation and transport inside membranes were assessed before- and after-washing assays by X-ray photoelectron spectroscopy depth profiling analysis. PMMA addition improved SNP fixation. Plasma-treated membranes showed higher hydrophilicity. Anti-biofouling activity was successfully achieved against Gram-positive (Enterococcus faecalis) and -negative (SalmonellaTyphimurium) bacteria. Therefore, disinfection by ultrafiltration showed substantial resistance to biofouling. The post-synthesis functionalization process developed provides a more efficient fabrication route for anti-biofouling and anti-bacterial membranes used in the water treatment field. To the best of our knowledge, this is the first report of a gas phase condensation process combined with a PECVD procedure in order to deposit SNP on commercial membranes to inhibit biofouling formation.
authors.affiliation: Instituto de Investigaciones para la Industria Química, Consejo Nacional de Investigaciones en Ciencia y Técnica y Facultad de Ingeniería, Universidad Nacional de Salta. Av. Bolivia 5150, A4408FVY Salta Capital, Argentina.
authors.forename: Mercedes Cecilia
authors.initials: MC
authors.lastname: Cruz
authors.affiliation: Centro Atómico Bariloche, CNEA, Av. Bustillo 9500, 8400, S. C. de Bariloche, Río Negro, Argentina.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Ruano
authors.affiliation: Technische Universität Dresden - Institut für Festkörperelektronik, 01062 Dresden, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Wolf
authors.affiliation: Technische Universität Dresden - Institut für Festkörperelektronik, 01062 Dresden, Germany ; Fraunhofer-Institut für Elektronenstrahl- und Plasmatechnik, 01277 Dresden, Germany.
authors.forename: Dominic
authors.initials: D
authors.lastname: Hecker
authors.affiliation: Instituto de Investigaciones para la Industria Química, Consejo Nacional de Investigaciones en Ciencia y Técnica y Facultad de Ingeniería, Universidad Nacional de Salta. Av. Bolivia 5150, A4408FVY Salta Capital, Argentina.
authors.forename: Elza Castro
authors.initials: EC
authors.lastname: Vidaurre
authors.affiliation: Technische Universität Dresden - Institut für Festkörperelektronik, 01062 Dresden, Germany.
authors.forename: Ralph
authors.initials: R
authors.lastname: Schmittgens
authors.affiliation: Instituto de Investigaciones para la Industria Química, Consejo Nacional de Investigaciones en Ciencia y Técnica y Facultad de Ingeniería, Universidad Nacional de Salta. Av. Bolivia 5150, A4408FVY Salta Capital, Argentina ; Fogarty International Center, University of California at Davis, U.S.
authors.forename: Verónica Beatriz
authors.initials: VB
authors.lastname: Rajal
keywords: XPS; biofouling; gas flow sputtering; plasma; silver nanoparticles; ultrafiltration