Bioactivity and antibacterial properties of calcium- and silver-doped coatings on 3D printed titanium scaffolds

• Published in: Surface & coatings technology Vol. 421; p. 127476
• Main Authors: Rodríguez-Contreras, Alejandra, Torres, Diego, Rafik, Belal, Ortiz-Hernandez, Monica, Ginebra, Maria Pau, Calero, José A., Manero, José María, Ruperez, Elisa
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.09.2021; Elsevier BV
• Subjects: 3D-printing; Adhesion; Antibacterial activity; Apatite; Bacteria; Biocompatibility; Biological activity; Biomaterials; Biomedical materials; Body fluids; Calcium titanate; Coatings; Cytotoxicity; E coli; Nanoparticles; Porous structures; Silver; Surgical implants; Three dimensional printing; Titanium; Titanium implants; Toxicity; Silver; Antibacterial activity; Porous structures; 3D-printing; Titanium implants; Biomaterials
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2021.127476

One of the major problems faced by metallic implants is the high probability of bacterial infections, with significant consequences for the patient. In this work, a thermochemical treatment is proposed to obtain silver-doped calcium titanate coatings on the Ti surface to improve the bioactivity of porous 3D-printed Ti structures and simultaneously provide them with antibacterial properties. A complete characterization of the new coating, the study of the ion release and the analysis of its cytotoxicity were carried out together with evaluation of the natural apatite forming in simulated body fluid (SBF). Moreover, the antibacterial properties of the coatings were assessed against Pseudomona aeruginosa and Escherichia coli as gram-negative and Staphylococcus aureus and Staphylococcus epidermidis as gram-positive bacterial strains. Ag ions were integrated into the Ca titanate layer and Ag nanoparticles were formed within the entire 3D Ti surface. Ca and Ag ions were released from both porous and solid samples into the Hanks' solution for 48 h. The treated surfaces showed no cytotoxicity and an apatite layer precipitated on the entire porous surface when the samples were immersed in SBF. The release of Ag from the surface had a strong antibacterial effect and prevented bacterial adhesion and proliferation on the surface. Moreover, the nanostructured topography of the coating resulted also in a reduction of bacterial adhesion and proliferation, even in absence of Ag. In conclusion, the cost-effective approach here reported provided protection against the most predominant bacterial colonizers to the Ti porous implants, while maintaining their bioactivity. •Thermochemical process for porous orthopedic implants provides antibacterial effect.•Ag was introduced into a bioactive Ca titanate layer on 3D-printed porous structure.•Ca titanate containing Ag provided bioactivity and antibacterial properties.•Apatite precipitated on the surface of the entire 3D-printed porous Ti structure.•There is an effect of the produced topography on the bacterial attachment.