Surface Modification of Titanium Alloys with Nanopores to Enhance the Antimicrobial Properties

Orthopedic infection is one of the leading reasons behind orthopedic implant failure, followed by lack of osseointegration. Bacterial surgical site infection (SSI), which raises the risk of patient morbidity, numerous procedures, and possibly paralysis, is one of the most prevalent orthopedic implant complications. Titanium and its alloys are often employed as orthopedic implants to make use of their biocompatible and mechanical properties, that stand superior to other metals. The study aims to investigate the gentamicin-coated titanium oxide nanotube arrays’ potential antibacterial properties. Anodization represents a promising method for creating precisely controlled nanotubes on implant surfaces. These nanotubes serve as localized drug delivery channels and function as active drug reservoirs, effectively impeding bacterial colonization and infections in implant. The nanosurface, in addition, promotes cell adhesion and proliferation. In this study, titanium implant material is made bioactive through a coating of niobium (Zr). Depending on the atomic weight percentage of the Zr, the coating contained varied weight percentages namely 5%, 10%, and 15% of Nb. Following this, the substrates are anodized using a graphite counter electrode and an ammonium fluoride electrolyte solution at different voltages between 60 and 80 V for 60 min. The scanning electron microscope (SEM) was utilized to examine the microstructure of the fabricated nanotubes. The nanotubes on the surface of the Ti substrates with Zr coating by magnetron sputter had a nanotube diameter ranging from 80–140 nm and a coating thickness of 1–3.5 µm. To achieve the prolonged drug delivery, co-precipitation coatings were used to load gentamicin drug along with the SBF into anodized Ti substrates. The drug-loaded anodized Ti samples were shown to obey first-order dissolution kinetics, exhibiting burst release followed by sustain release. This paper will explain the impact of titanium nanotube diameter on the loading/release of gentamicin by co-precipitation technique and the resistance of Staphylococcus aureus and Escherichia coli evaluated.