An extended spectrum bactericidal titanium dioxide (TiO2) coating for metallic implants: in vitro effectiveness against MRSA and mechanical properties

Abstract

Implant infections remain feared and severe complications after total joint arthroplasty. The incidence of multi-resistant pathogens, causing such infections, is rising continuously, and orthopaedic surgeons are confronted with an ever-changing resistance pattern. Anti-infectious surface coatings aim for a high local effective concentration and a low systemic toxicity at the same time. Antibacterial efficacy and biomechanical stability of a novel broad-spectrum anti-infectious coating is assessed in the present study. Antibacterial efficacy of a sol-gel derived titanium dioxide (TiO(2)) coating for metal implants with and without integrated copper ions as antibiotic agent was assessed against methicillin resistant Staphylococcus aureus (MRSA 27065). Both bacterial surface adhesion and growth of planktonic bacteria were assessed with bare and various TiO(2)-coated Ti6Al4V metal discs. Furthermore, bonding strength of the TiO(2) surface coating, using standard testing procedures, as well as surface roughness were determined. We found a significant reduction of the bacterial growth rate for the coatings with integrated copper ions, with highest reduction rates observed for a fourfold copper TiO(2)-coating. Pure TiO(2) without integrated copper ions did not reduce bacterial growth compared to uncoated Ti6Al4V. The coating was not detached from the substrate by standard adhesive failure testing, which indicated an excellent durability of the implant coating. The TiO(2) coating with integrated copper ions could offer a new strategy for preventing implant-associated infections, with antibacterial properties not only against the most common bacteria causing implant infections but also against multiresistant strains such as MRSA.

Titanium Oxide Antibacterial Surfaces in Biomedical Devices

“…Furthermore, the TiO 2 -coated orthodontic wires had a bactericidal effect on both strains; since one of the main causes of failure in orthodontic treatment is the development of dental plaque initiated by the adhesion of S. mutans to the tooth surface or orthodontic devices, this treatment appears of particular interest for this specific device (64). This example allows us to point out that materials other than Ti alloys can be treated in order to add a thin titanium oxide layer onto their surface: results of this sort have been achieved by other authors on different organic and inorganic substrates (4,(70)(71)(72)(73). Another advantage of using the sol-gel technique is the possibility of incorporating metal ions, nanometric clusters, and bactericidal molecules that in most cases have antibacterial properties per se, namely Ag ions/nanoparticles (61,63,(74)(75)(76), or Cu ions (69,73).…”

Antibacterial and Biocompatible Titanium-Copper Oxide Coating May Be a Potential Strategy to Reduce Periprosthetic Infection: An In Vitro Study

“…Antibacterial Activity Using a previously described method [13,16], discs were submerged in separate wells containing 2 mL Roswell Park Fig. 1 This schematic drawing shows the characteristics of the closed-field unbalanced magnetron sputtering system used for TiCuO coating depositions.…”

CORR Insights®: Antibacterial and Biocompatible Titanium-Copper Oxide Coating May Be a Potential Strategy to Reduce Periprosthetic Infection: An In Vitro Study

“…In fact, the US Environmental Protection Agency approved hundreds of such alloys for use on touch surfaces, such as door knobs, push plates, and railings. Interestingly, few studies have worked to extend the use of copper alloys to the surfaces of arthroplasty implants [3][4][5]. In this paper, Narambuena and colleagues have demonstrated as a ''proof-ofconcept'' that coating a titanium alloy with a thin film of titanium-copper oxide does provide antibacterial properties, with minimal osteoblast cellline toxicity.…”