title: Electrochemical and morphological investigation of silver and zinc modified calcium phosphate bioceramic coatings on metallic implant materials.
abstract: In our research nanostructured silver and zinc doped calcium-phosphate (CaP) bioceramic coatings were prepared on commonly used orthopaedic implant materials (Ti6Al4V). The deposition process was carried out by the pulse current technique at 70 °C from electrolyte containing the appropriate amount of Ca(NO3)2 and NH4H2PO4 components. During the electrochemical deposition Ag(+) and Zn(2+) ions were introduced into the solution. The electrochemical behaviour and corrosion rate of the bioceramic coatings were investigated by potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) measurements in conventional Ringer's solution in a three electrode open cell. The coating came into contact with the electrolyte and corrosion occurred during immersion. In order to achieve antimicrobial properties, it is important to maintain a continuous release of silver ions into physiological media, while the bioactive CaP layer enhances the biocompatibility properties of the layer by fostering the bone cell growth. The role of Zn(2+) is to shorten wound healing time. Morphology and composition of coatings were studied by Scanning Electron Microscopy, Transmission Electron Microscopy and Energy-dispersive X-ray spectroscopy. Differential thermal analyses (DTA) were performed to determine the thermal stability of the pure and modified CaP bioceramic coatings while the structure and phases of the layers were characterized by X-ray diffraction (XRD) measurements.
authors.affiliation: Bay Zoltán Nonprofit Ltd. for Applied Research, H-1116 Budapest, Fehérvári u. 130, Hungary. Electronic address: monika.furko@bayzoltan.hu.
authors.forename: M
authors.initials: M
authors.lastname: Furko
authors.affiliation: Institute of Particle Science and Engineering, University of Leeds, LS2 9JT, UK.
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Institute of Particle Science and Engineering, University of Leeds, LS2 9JT, UK.
authors.forename: T A
authors.initials: TA
authors.lastname: Wilkins
authors.affiliation: Bay Zoltán Nonprofit Ltd. for Applied Research, H-1116 Budapest, Fehérvári u. 130, Hungary.
authors.forename: C
authors.initials: C
authors.lastname: Balázsi
mesh_terms: D000497:Alloys; D002130:Calcium Phosphates / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000494:pharmacology; D003343:Corrosion; D058266:Dielectric Spectroscopy; D004573:Electrolytes / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D012834:Silver / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties; D013818:Thermogravimetry; D014025:Titanium / Q000737:chemistry; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry*
chemical_list: D000497:Alloys; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D004573:Electrolytes; C031462:titanium alloy (TiAl6V4); D012834:Silver; C020243:calcium phosphate; D014025:Titanium; D015032:Zinc
keywords: Biomedical implants; Calcium phosphate bioceramic; Electrochemical Impedance Spectroscopy; Hydroxyapatite; Pulse plating technique