Innovative Bioactive Nanocomposite Coatings on Titanium with Enhanced Corrosion Resistance and Biological Performance

Abstract This study introduces a novel nanocomposite coating of tri-calcium phosphate (TCP), Acacia arabica extract (AA), polyvinyl alcohol (PVA), and silver nanoparticles (Ag-NPs) for titanium implants. Titanium’s use in biomedical applications is limited by its susceptibility to chloride-induced corrosion in simulated body fluid (SBF), which reduces bioactivity, may trigger inflammation, and offers inadequate antibacterial protection, potentially leading to implant failure. To address these challenges, the nanocomposite was synthesized via a green method and deposited on titanium using electrophoretic deposition (EPD). Electrochemical evaluations, including open circuit potential (OCP), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS), demonstrated marked corrosion protection, with inhibition efficiencies of 83.00% (PDP) and 95.18% (EIS). Surface characterization by UV-Vis, X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) confirmed successful, uniform coating deposition. Water contact angle measurements revealed enhanced hydrophilicity (54.2°) compared to uncoated Ti (67.5°), and adhesion testing indicated strong bonding with a pull-off strength of 5.1 MPa. Biological assessments confirmed potent antibacterial activity and reduced cytotoxicity, demonstrating the coating’s potential to improve implant performance. This work highlights TCP/AA/PVA/Ag-NPs as a promising multifunctional coating strategy to enhance titanium’s corrosion resistance, antibacterial efficacy, and biocompatibility for biomedical applications.