title: Correlation between surface physicochemical properties and the release of iron from stainless steel AISI 304 in biological media.
abstract: Stainless steel is widely used in biological environments, for example as implant material or in food applications, where adsorption-controlled ligand-induced metal release is of importance from a corrosion, health, and food safety perspective. The objective of this study was to elucidate potential correlations between surface energy and wettability of stainless steel surfaces and the release of iron in complexing biological media. This was accomplished by studying changes in surface energies calculated from contact angle measurements, surface oxide composition (X-ray photoelectron spectroscopy), and released iron (graphite furnace atomic absorption spectroscopy) for stainless steel grade AISI 304 immersed in fluids containing bovine serum albumin or citric acid, and non-complexing fluids such as NaCl, NaOH, and HNO3. It was shown that the surface wettability and polar surface energy components were all influenced by adventitious atmospheric carbon (surface contamination of low molecular weight), rather than differences in surface oxide composition in non-complexing solutions. Adsorption of both BSA and citrate, which resulted in ligand-induced metal release, strongly influenced the wettability and the surface energy, and correlated well with the measured released amount of iron.
authors.affiliation: KTH Royal Institute of Technology, Dept. Chemistry, Div. Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden. Electronic address: yolanda@kth.se.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Hedberg
authors.affiliation: KTH Royal Institute of Technology, Dept. Chemistry, Div. Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden.
authors.forename: Maria-Elisa
authors.initials: ME
authors.lastname: Karlsson
authors.affiliation: KTH Royal Institute of Technology, Dept. Chemistry, Div. Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden; SP Technical Research Institute of Sweden, Chemistry, Materials and Surfaces, P.O. Box 5607, SE-114 86 Stockholm, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Blomberg
authors.affiliation: KTH Royal Institute of Technology, Dept. Chemistry, Div. Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden.
authors.forename: Inger
authors.initials: I
authors.lastname: Odnevall Wallinder
authors.affiliation: KTH Royal Institute of Technology, Dept. Chemistry, Div. Surface and Corrosion Science, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Hedberg
mesh_terms: D007501:Iron / Q000378:metabolism*; D013054:Spectrophotometry, Atomic; D013193:Stainless Steel; D013499:Surface Properties
chemical_list: D013193:Stainless Steel; D007501:Iron
keywords: Adsorption; Corrosion; Metal release; Protein; Stainless steel; Surface chemistry