Effect of electrochemical oxidation and drug loading on the antibacterial properties and cell biocompatibility of titanium substrates

Abstract

A combination of $${\text{ TiO}}_{2}$$ TiO 2 nanotube array (TON) and controlled drug release system is employed to provide enhanced surface properties of titanium implants. Electrochemical anodization process is used to generate TON for introducing, vancomycin, an effective antibacterial drug against Staphylococcusaureus. TON loaded vancomycin is then coated with a number of layers of 10% gelatin using spin coating technique. The gelatin film is reinforced with graphene oxide (GO) nanoparticles to improve the surface bioactivity. The surface of the samples is characterized by field emission electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), and contact angle measurement. The results illustrate that the TON was constructed and vancomycin molecules are successfully loaded. The drug release study shows that the amount of released vancomycin is controlled by the thickness of gelatin layers. With an increase in gelatin film layers from 3 to 7, the release of vancomycin in the burst release phase decreased from 58 to 31%, and sustained release extended from 10 to 17 days. The addition of GO nanoparticles seems to reduce drug release in from 31 to 22% (burst release phase) and prolonged drug release (from 17 to 19 days). MTT assay indicates that samples show no cytotoxicity, and combination of GO nanoparticles with gelatin coating could highly promote MG63 cell proliferation. Soaking the samples in SBF solution after 3 and 7 days demonstrates that hydroxy apatite crystals were deposited on the TON surface with GO-gelatin coating more than surface of TON with gelatin. Moreover, based on the results of disc diffusion assay, both samples (loaded with Vancomycin and coated with gelatin and gelatin-GO) with the inhibition zones equaled to 20 mm show effective antibacterial properties against S. aureus. The evidence demonstrates that titania nanotube loaded with vancomycin and coated with gelatin-GO has a great potential for general applicability to the orthopedic implant field.

Characterization and investigation of electrochemical and biological properties of antibacterial silver nanoparticle-deposited TiO2 nanotube array surfaces

“…Thus, these oxide structures in the nanotube structures are transformed from amorphous to crystalline form without any morphological difference under low temperature conditions with by a diffusion mechanism. In our previous works 40 , 52 , the anodic oxidation mechanisms under the existence of fluoride ions were discussed in detail. The AO process is the electrolysis of water at the first reaction.…”

Surface characterization, electrochemical properties and in vitro biological properties of Zn-deposited TiO2 nanotube surfaces

“…After AO process, the nanotube surfaces are transformed from amorphous to crystalline structures without any morphological variations by a diffusion mechanism through 60 min at 450 °C as described in experimental section. In our previous works 48 , 55 , 56 , the AO formation mechanisms under the existence of F - were discussed in detail. The AO process is the electrolysis of H 2 O at initial reactions.…”

Solid-State Dewetting of Thin Au Films for Surface Functionalization of Biomedical Implants

“…While STEM elemental mapping provides evidence of continuous film formation at the nanoscale (Figure 4), AFM scans and roughness measurements (Figure 7) illustrate the continuity of the film at the micrometer scale. The developed approach to surface functionalization vial solid-state DW is simpler and more versatile compared to previously reported methods of Ti-based surface functionalization with VH by drop casting [40,41], cathodic electrophoretic deposition [42], and electrochemical deposition [43]. Moreover, it enables the fabrication of other metallic NPs, e.g., Ag, magnesium (Mg), iron (Fe), and zinc (Zn) employed in biomedical applications.…”

“…Further investigations pertaining to mechanical stability, as well as chemical stability within physiological solutions, must be undertaken to elucidate the potential of the developed functional layer in the context of implantable applications. The developed approach to surface functionalization vial solid-state DW is simpler and more versatile compared to previously reported methods of Ti-based surface functionalization with VH by drop casting [40,41], cathodic electrophoretic deposition [42], and electrochemical deposition [43]. Moreover, it enables the fabrication of other metallic NPs, e.g., Ag, magnesium (Mg), iron (Fe), and zinc (Zn) employed in biomedical applications.…”