title: Changing bioperformance of TiO2 amorphous nanotubes as an effect of inducing crystallinity.
abstract: Controlled-diameter TiO(2) nanotubes were obtained by electrochemical anodizing of two different substrates (Ti and Ti6Al7Nb) in an aqueous electrolyte. As-formed TiO(2) nanotubes are amorphous and by subjecting to thermal treatments, the structure becomes crystalline. An optimal thermal treatment with a specific anatase/rutile ratio was chosen, determined from X-ray diffraction (XRD). The electrochemical behaviour of annealed and as-formed samples was followed with Tafel plots and Electrochemical impedance spectroscopy (EIS), while surface analysis involved scanning electron microscopy (SEM) and contact angle measurements (CA). Annealed samples have a more hydrophilic character than as-formed as well as a better stability in bioliquids. Such behaviour of annealed samples is connected with a better biocompatibility expressed in terms of cell morphology and gene expression of bone specific markers obtained from Reverse Transcription Polymerase Chain Reaction (RT-PCR).
authors.affiliation: University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Bucharest, Romania. anca_mazare@yahoo.co.uk
authors.forename: A
authors.initials: A
authors.lastname: Mazare
authors.forename: M
authors.initials: M
authors.lastname: Dilea
authors.forename: D
authors.initials: D
authors.lastname: Ionita
authors.forename: I
authors.initials: I
authors.lastname: Titorencu
authors.forename: V
authors.initials: V
authors.lastname: Trusca
authors.forename: E
authors.initials: E
authors.lastname: Vasile
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D045744:Cell Line, Tumor; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis* / Q000494:pharmacology; D003460:Crystallization; D058266:Dielectric Spectroscopy; D004573:Electrolytes; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D058574:Integrin-Binding Sialoprotein / Q000235:genetics / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D015675:Osteocalcin / Q000235:genetics / Q000378:metabolism; D015676:Osteonectin / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053838:Scattering, Small Angle; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D015415:Biomarkers; D020099:Coated Materials, Biocompatible; D004573:Electrolytes; D058574:Integrin-Binding Sialoprotein; D015676:Osteonectin; D012333:RNA, Messenger; D014867:Water; D015675:Osteocalcin; C070282:Ti-6Al-7Nb alloy; C009495:titanium dioxide; D014025:Titanium