Novel chitosan composite coatings containing titania nanoparticles (n-TiO 2 ) for biomedical applications were developed by electrophoretic deposition (EPD) from ethanol-water suspensions. The optimal ethanol-water ratio was studied in order to avoid bubble formation during the EPD process and to ensure homogeneous coatings. Different n-TiO 2 contents (0.5-10 g L 21) were studied for a fixed chitosan concentration (0.5 g L 21) and the properties of the electrophoretic coatings obtained were characterized.Coating composition was analyzed by thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) was employed to study both the surface and the cross section morphology of the coatings, and the thicknesses (2-6 mm) of the obtained coatings were correlated with the initial ceramic content. Contact angle measurements, as a preliminary study to predict hypothetic protein attachment on the coatings, were performed for different samples and the influence of a second chitosan layer on top of the coatings was also tested. Finally, the electrochemical behavior of the coatings, evaluated by polarization curves in DMEM at 37 uC, was studied in order to assess the corrosion resistance provided by the n-TiO 2 /chitosan coatings.

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Two alginate (Alg) based composite coatings on stainless steel AISI 316L substrates, one containing titania nanoparticles (n-TiO 2 ) and another one a mixture (50/50 wt-%) of n-TiO 2 and bioactive glass (BG), intended for biomedical applications, were developed by electrophoretic deposition (EPD) from ethanol/water suspensions. Different n-TiO 2 (2-10 g L 21 ) and BG (1-5 g L 21 ) contents were studied for a fixed alginate concentration (2 g L 21 ), and the properties of the electrophoretically obtained coatings were characterised. Coatings with high ceramic content (up to 67 vol.-%) were obtained. The presence of BG particles improves the mechanical properties of the coatings by increasing the adhesion to the substrate and also accelerates the formation of hydroxyapatite after immersion of the coatings in simulated body fluid. The electrochemical behaviour of the coated substrates, evaluated by polarisation curves in Dulbecco's modified eagle medium at 37uC, confirmed the corrosion protection function of the novel EPD coatings. The present polymer-ceramic composite coatings belong to an emerging family of bioactive, compliant coatings that are promising for a range of biomedical applications.

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