Synthesis of nanotubular oxide on Ti-24Zr-10Nb-2Sn as a drug-releasing system to prevent the growth of Staphylococcus aureus

The aim in the present study was to explore the potential application of titanium nanotubes developed in the Ti-24Zr-10Nb-2Sn alloy, as drug delivery systems to prevent bacterial infections in medical devices. A nanotubular oxide layer was synthesized by electrochemical anodizing on the Ti-24Zr-10Nb-2Sn superelastic alloy and the electrical variables that control the growth at constant potential were determined. Scanning electron microscopy (SEM) showed that the nanostructures show a positive linear growth as a function of the applied potential, the superficial analysis carried out by X-ray photoelectron spectroscopy (XPS) showed different states of valence evidencing the presence of TiO2, Nb2O5, SnO2, and ZrO2. FTIR spectra confirm the presence of the antibiotic gentamicin in the Ti-24Zr-10Nb-2Sn nanotubes. The developed nanostructures were evaluated in a phosphate buffer solution (PBS) as a controlled release system of antibiotics. It was observed by bacteriological tests that the nanostructured morphology in combination with the chemical composition has bacteriostatic properties; while the release of the antibiotic-loaded inside the nanotubes had a bactericidal effect. The results showed that it is possible to grow and control the morphology of the developed nanostructures on Ti-24Zr-10Nb-2Sn, which can be used for orthopedic purposes to transport and control the local release of molecules like antibiotics at the site of interest and thus prevent postoperative infections.