title: Human saliva forms a complex film structure on alumina surfaces.
abstract: Films formed from saliva on surfaces are important for the maintenance of oral health and integrity by protection against chemical and/or biological agents. The aim of the present study was to investigate adsorbed amounts, thickness, and structure of films formed from human whole saliva on alumina surfaces by means of in situ ellipsometry, neutron reflectivity, and atomic force microscopy. Alumina (Al2O3, synthetic sapphire) is a relevant and interesting substrate for saliva adsorption studies as it has an isoelectric point close to that of tooth enamel. The results showed that saliva adsorbs rapidly on alumina. The film could be modeled in two layers: an inner and dense thin region that forms a uniform layer and an outer, more diffuse and thicker region that protrudes toward the bulk of the solution. The film morphology described a uniformly covering dense layer and a second outer layer containing polydisperse adsorbed macromolecules or aggregates.
authors.affiliation: Surface Chemistry, Biomedical Laboratory Science, Faculty of Health and Society, Malmö University, Malmö, Sweden.
authors.forename: Marité
authors.initials: M
authors.lastname: Cárdenas
authors.forename: Thomas
authors.initials: T
authors.lastname: Arnebrant
authors.forename: Adrian
authors.initials: A
authors.lastname: Rennie
authors.forename: Giovanna
authors.initials: G
authors.lastname: Fragneto
authors.forename: Robert K
authors.initials: RK
authors.lastname: Thomas
authors.forename: Liselott
authors.initials: L
authors.lastname: Lindh
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D001703:Biophysics / Q000379:methods; D003764:Dental Materials / Q000737:chemistry; D006801:Humans; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D009502:Neutrons; D012463:Saliva / Q000378:metabolism*; D012471:Salivary Proteins and Peptides / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D003764:Dental Materials; D012471:Salivary Proteins and Peptides; D000537:Aluminum Oxide