Antibacterial and biocompatible behavior of Ti6Al4V and geopolymer-coated Ti6Al4V functionalized with c[RGDfK]

• Geopolymer-based coatings on titanium-based alloys address critical challenges in orthopedics. • Geopolymer with c[RGDfK] peptide supports osteoblastic cell adhesion and proliferation. • Coatings exhibit antibacterial activity against Gram-positive and Gram-negative bacteria. • Coatings may improve the performance and safety of titanium-based orthopedic implants. Titanium alloys, especially Ti6Al4V, are widely used in biomedical applications for bone applications due to their superior mechanical properties and biocompatibility. However, challenges such as bacterial infections and poor osseointegration may undermine their long-term performance. In this study, we explored the functionalization of geopolymer-coated titanium alloys with the peptide c[RGDfK], known for enhancing cell adhesion and promoting osteointegration, alongside the introduction of antibacterial properties. Geopolymer coatings were applied to titanium alloy substrates, then functionalized with c[RGDfK] peptide to create a multifunctional surface. The coatings were characterized by their surface morphology, wettability, and biocompatibility. The peptide-functionalized coatings enhanced osteoblast-like cells (MG63 cells) adhesion, spreading, and proliferation, demonstrating the potential for improved biocompatibility. Furthermore, antibacterial activity was evaluated against both Gram-positive ( S. epidermidis ) and Gram-negative ( E. coli ) bacteria. The results showed that the geopolymer coating, coupled with c[RGDfK] functionalization, significantly improved bacterial inhibition, reducing bacterial adhesion and proliferation on the surface. This novel approach combines the advantages of geopolymer coatings, peptide functionality, and antibacterial properties, providing a promising strategy for the development of titanium-based biomedical implants with improved infection resistance. These findings offer significant implications for the design of advanced implant surfaces aimed at optimizing the biological functionality of different medical devices.