title: Structural characterization of self-assembled polypeptide films on titanium and glass surfaces by atomic force microscopy.
abstract: Chemically modified biomaterial surfaces (titanium and glass) covered with polyelectrolyte self-assembled films formed by the alternating adsorption of cationic poly-L-lysine (PLL) and anionic poly-L-glutamic acid (PGA) were structurally characterized by atomic force microscopy. Complementary information concerning the thickness and layer-by-layer growth of the films was provided by optical waveguide light-mode spectroscopy. The frequently used ex situ and the rarely used in situ build-up methods were compared. Important aspects of the industrial applicability of these films, their stability in time, and possible differences in their morphology were investigated. The films revealed a granular pattern, with grain diameters of 270 +/- 87 nm for glass (up to 8 bilayers) and 303 +/- 89 nm for titanium (up to 10 bilayers), independently of the build-up procedure. Both surfaces displayed a rehydration capability, the titanium surface exhibiting a better stability in time. The high roughness values observed at acidic or basic pH are related to the degree of ionization of PGA and PLL.
authors.affiliation: Department of Dentistry and Oral Surgery, University of Szeged, Tisza Lajos krt. 64, H-6720 Szeged, Hungary.
authors.forename: István
authors.initials: I
authors.lastname: Pelsöczi
authors.forename: Kinga
authors.initials: K
authors.lastname: Turzó
authors.forename: Csilla
authors.initials: C
authors.lastname: Gergely
authors.forename: András
authors.initials: A
authors.lastname: Fazekas
authors.forename: Imre
authors.initials: I
authors.lastname: Dékány
authors.forename: Frederic
authors.initials: F
authors.lastname: Cuisinier
mesh_terms: D000327:Adsorption; D001672:Biocompatible Materials / Q000737:chemistry*; D001673:Biodegradation, Environmental; D020099:Coated Materials, Biocompatible; D004573:Electrolytes; D005898:Glass / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D018625:Microscopy, Atomic Force / Q000379:methods*; D049329:Nanostructures; D010455:Peptides / Q000737:chemistry*; D011099:Polyglutamic Acid / Q000737:chemistry; D011107:Polylysine / Q000737:chemistry; D011108:Polymers; D013053:Spectrophotometry; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D004573:Electrolytes; D046911:Macromolecular Substances; D010455:Peptides; D011108:Polymers; D011107:Polylysine; D011099:Polyglutamic Acid; D014025:Titanium