The replacement of bone tissue for metallic implants has gained special interest in the last decades. However, there are implant that suffer corrosion, fatigue fracture, wear and incompatibility with host tissue, aspects that can be solved by superficial modification of the metallic substrates. Particularly, inorganic ceramic coatings such as hydroxyapatite (HAp, Ca10(PO4)6(OH)2) have been widely employed to improve the incompatibility. Nevertheless, the brittle nature and poor strength of HAp coating are a problem, especially when the implant need to work under load-bearing conditions. Therefore, the incorporation of nanoparticles as secondary bioactive fillers enhance their characteristics.

Thus, this work is based on the preparation of Sr/Ga nanoparticles by LDH and their incorporation on silicon substituted HAp coating as an active/passive filler. The nanoparticles would act as drug/ion release to increase the bioactivity and also to block the corrosive species and avoid the corrosion of the metallic substrate. For this purpose, Sr/Ga LDH nanoparticles has been synthesized using co-precipitation and ion exchange method. Then, surface of Ti substrates has been pre-treated by anodizing to increase the corrosion resistance and adhesion properties. The morphology, topology, composition, and electrochemical properties of the passivated surfaces have been characterized.

Finally, a Si-HAp coating loaded with Sr/Ga LDH nanoparticles has been electrophoretically deposited on anodized samples. The release ability of LDHs make them a desirable candidate as bioactive additive for bone regeneration. The flake morphology of these nanoparticles can enhance the barrier performance and the toughness of the HAp coating. The effect of LDH incorporation on the anticorrosion behaviour of Si-HAp coated Ti samples was studied by polarization and electrochemical impedance spectroscopy (EIS). Furthermore, the bioactivity and antibacterial performance of the composite coatings applied on Ti implant samples have also investigated.