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Despite the significant contribution of titanium and its alloys for hard tissue regenerative medicine, some major issues remain to be solved. Implants’ long-term stability is threatened by poor osseointegration. Moreover, bacterial adhesion and excessive inflammatory response are also to be considered in the design of a device intended to be integrated into the human body. Here, a cerium mixed oxide (CeO x ) coating was realized on pristine and nanotubular-structured Ti and Ti6Al4V surfaces using a simple layer-by-layer drop-casting technique. Bioactivity, resistance in simulated inflammatory conditions, and bactericidal capacity were evaluated as a function of morphological surface characteristics combined with the cerium quantity deposited. The results obtained suggest that the presence of CeO x on the surfaces with nanotubes enhanced osseointegration, while on the non-nanostructured surfaces, this coating improved resistance under oxidative stress and provided excellent antibacterial properties.

This work aims at preparing and characterizing a versatile multifunctional platform enabling the immobilization of macromolecules on a titanium surface by robust covalent grafting. Functionalized titanium is widely used in the biomedical field to improve its properties. Despite its high biocompatibility and osteointegrability, titanium implants are not very stable in the long term due to the onset of inflammation and bacterial infections. The proposed method allows the superficial insertion of three different organic linkers to be used as anchors for the attachment of biopolymers or bioactive molecules. This strategy used green solvents and is a good alternative to the proposed classic methods that employ organic solvents. The uniformly modified surfaces were characterized by micro-Fourier transform infrared spectroscopy (micro-FTIR), X-ray Photoelectron spectroscopy (XPS) and Near-Edge X-ray Absorption Fine Structure (NEXAFS). The latter made it possible to assess the orientation of the linker molecules with respect to the titanium surface. To test the efficiency of the linkers, two polymers (alginate and 2-(dimethylamino)-ethyl methacrylate (PDMAEMA)), with the potential ability to increase biocompatibility, were covalently attached to the titanium surfaces. The obtained results are a good starting point for the realization of stable polymeric coatings permanently bonded to the surface that could be used to extend the life of biomedical implants.