title: Influence of Oxynitrided Surface in the Production of a Less Susceptible Titanium Surface to Skin-Borne Bacterial Adhesion.
abstract: There is a growing quest for an ideal biomaterial that shows appropriate cellular response and is not susceptible to microbial adhesion. In this study, commercial grade II titanium was submitted to RF/DC plasma surface modification at 2.2 mbar, using gas mixtures of argon, nitrogen, and oxygen at proportions 4:1:2 and 4:1:3. The surfaces were physically and chemically characterized. In order to evaluate bacterial response, the surfaces were exposed to Staphylococcus epidermidis. Oxynitrided samples, although having a higher roughness as compared with untreated samples, exhibited lower bacterial growth. This observation is probably due to the formation of different crystalline phases of nitrides and oxides caused by plasma treatment. The surface with highest contact angle and highest surface tension showed lower bacterial adhesion. These results were confirmed by scanning electron microscopy. The role of nitrogen in reducing bacterial adhesion is clear when this material is compared with untreated titanium, on which only an oxide film is present.
authors.affiliation: Lab Plasma, Federal University of Rio Grande do Norte, Rio Grande do Norte, Brazil.
authors.forename: Michelle de Medeiros
authors.initials: Mde M
authors.lastname: Aires
authors.affiliation: Biofilms and Microbial Diversity Laboratory, Biotechnology Center and Pharmacy College of the Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil.
authors.forename: Janine
authors.initials: J
authors.lastname: Treter
authors.affiliation: Lab Plasma, Federal University of Rio Grande do Norte, Rio Grande do Norte, Brazil.
authors.forename: Danilo Cavalcante
authors.initials: DC
authors.lastname: Braz
authors.affiliation: Physical Institute, Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Krug
authors.affiliation: Biofilms and Microbial Diversity Laboratory, Biotechnology Center and Pharmacy College of the Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil.
authors.forename: Alexandre José
authors.initials: AJ
authors.lastname: Macedo
authors.affiliation: Lab Plasma, Federal University of Rio Grande do Norte, Rio Grande do Norte, Brazil.
authors.forename: Clodomiro
authors.initials: C
authors.lastname: Alves Júnior
mesh_terms: D001422:Bacterial Adhesion; D001672:Biocompatible Materials / Q000737:chemistry*; D018441:Biofilms / Q000254:growth & development; D006801:Humans; D008422:Materials Testing; D009584:Nitrogen / Q000737:chemistry; D010087:Oxides / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D058626:Plasma Gases / Q000737:chemistry*; D012867:Skin / Q000382:microbiology; D013203:Staphylococcal Infections / Q000382:microbiology; D013212:Staphylococcus epidermidis / Q000166:cytology / Q000502:physiology*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D010087:Oxides; D058626:Plasma Gases; D014025:Titanium; D009584:Nitrogen; D010100:Oxygen
keywords: Biofilm; Plasma; Staphylococcus epidermidis; Titanium