N-halamine-based multilayers on titanium substrates for antibacterial application

Schematic illustration of LBL(Cl) multilayer preparation and in vivo antibacterial application. [Display omitted] •Chi-HDH-Cl/Gel multilayer are deposited on titanium substrates via layer-by-layer assembly technique.•The modified titanium substrates present good antibacterial activity against E. coli and S. aureus.•The modified titanium substrates have desirable cytocompatibility in respect to osteoblasts. Bacterial infection is one of the most severe postoperative complications leading to clinical orthopedic implants failure. To improve the antibacterial property of titanium (Ti) substrates, a bioactive coating composed of chitosan-1-(hydroxymethyl)- 5,5-dimethylhydantoin (Chi–HDH-Cl) and gelatin (Gel) was fabricated via layer-by-layer (LBL) assembly technique. The results of Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1HNMR) and X-ray photoelectron spectroscopy (XPS) showed that Chi−HHD-Cl conjugate was successfully synthesized. Scanning electron microscopy (SEM), atomic force microscope (AFM) and water contact angle measurements were employed to monitor the morphology, roughness changes and surface wettability of Ti substrates, which proved the multilayers coating formation. Antibacterial assay against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) revealed that the Gel/Chi–HDH-Cl modified Ti substrates most efficiently inhibited the adhesion and growth of bacteria. Meanwhile, in vitro cellular tests confirmed that Gel/Chi–HDH-Cl multilayers had no obvious cytotoxicity to osteoblasts. The study thus provides a promising method to fabricate antibacterial Ti-based substrates for potential orthopedic application.