This communication shows a review of the main results of a collaborative work of interdisciplinarynature. The research is focused on the preparation of new sol-gel thin films for improving corrosionresistance and biocompatibility of Ti6Al4V alloys. With this aim, different strategies are beingapplied. For example, mixtures of two organopolysiloxane precursors are being used for thepreparation of sol-gel matrix of coatings: tetramethylortosilicate as inorganic precursor of thenetwork, and γ-methacryloxypropyltrimethoxysilane or γ-glycidoxypropyltrimethoxysilane asinorganic precursors. The resulting sol-gel coatings are modified with zirconium tetrabutoxide ortitanium isopropoxide as precursors of Zr and TiO_2 micro- and nano-particles for improving theiractive corrosion protection or self-healing properties. Another important part of the study isconsisting in using triethylphosphite and dimethylsilylphosphite to introduce phosphorus intoorganic–inorganic hybrid silica network for improving the bioactivity and biocompatibility of the solgelcoatings. The incorporation effect of the different dopant additives on the physicochemicalproperties is studied with different characterization techniques. Thermal stability of the hybrids isbeen examined by using thermogravimetric analysis (TG/DTG). Attenuated total reflectance FourierTransformer Infrared Spectroscopy (FTIR-ATR) is been applied for studying the functional groupswithin the matrix of the prepared sol-gel coatings. Scanning Electron Microscopy (SEM) coupledwith an Energy Dispersive X-ray (EDX) areapplied to study the surface morphology andcomposition of coated samples. Normal human osteoblast (NHOst) response in terms ofosteoblast viability and adhesion tests of coatings to the Ti6Al4V alloys routinely used in medicalimplants are used in the study. Fibrinogen has been chosen as a model for the for proteinadsorption studies on the coated surfaces. Corrosion resistance of the prepared coatings duringimmersion tests in simulated body fluids (SBF) is been studied by applying. For this purpose globalElectrochemical Impedance Spectroscopy (EIS) at macroscopic scale and local impedancespectroscopy (LEIS) at sub-millimeter and sub-microscopic scales are been applied. TG/DTGresults are indicating that the addition of the dopants used for these studies do not have a negativeinfluence on the coating stability. Addition of phosphorous precursors to TMOS-MAPTMS hybridsdramatically increased the rate of intermolecular condensation and cross-linking improving thebarrier properties of coatings. The study is showing that some of these sol-gel coatings displayexcellent bioactivity when soaked in the (SBF) and good corrosion protection behaviour and can bepotentially applicable for the manufacture of new implant materials for biomedical uses.
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