Antibacterial activity and cytocompatibility of Cu–Ti–O nanotubes

Abstract

TiO2 nanotubes (NTs) have favorable biological properties, but the poor antibacterial activity limits their application especially in orthopedics fields. In this article, Cu-Ti-O nanotubes with different Cu contents are fabricated on sputtered TiCu films. Scanning electron microscopy reveals the NTs can be formed on sputtered TiCu films when the Cu content is less than 14.6 at %. X-ray photoelectron spectroscopy results indicate the NTs are consist of CuO mixed with TiO2 and the Cu content in NTs decreases dramatically compared with that in TiCu films. Biological experiments show that although these NTs have poor release antibacterial activity, their contact antibacterial activity has proven to be excellent, indicating the NT surface can effectively inhibit biomaterial-associated infections. The cytocompatibility of the NTs is closely related to the Cu content and when its content is relatively low (1.01 at %), there is no appreciable cytotoxicity. So Cu-Ti-O NTs with 1 at % Cu may be suitable to achieve proper antibacterial activity and desired cytocompatibility. The Cu-Ti-O NTs integrate the favorable antibacterial activity of Cu and excellent biological properties of TiO2 NTs therefore have potential applications in orthopedics, dentistry, and other biomedical fields.

Review of Antibacterial Activity of Titanium-Based Implants’ Surfaces Fabricated by Micro-Arc Oxidation

“…Meanwhile, the osteoblastic adhesion, spreading, early proliferation and late differentiation on Cu-TiO 2 coatings were significantly enhanced due to the existence of the porous nano-structured surface produced during MAO, just like those found by other researchers [81,94]. Besides, the Cu element also plays a vital role in various cell behaviors, including osteoblasts [95], endothelial cells [96], bone marrow stem cells [63] and fibroblasts [64].…”

“…Besides, the Cu element also plays a vital role in various cell behaviors, including osteoblasts [95], endothelial cells [96], bone marrow stem cells [63] and fibroblasts [64]. Figure 11a, the coatings still maintained the typical porous structure of MAO, and Cu content on the surface of the sample increased with the increase of the concentration of Cu(CH3COO)2 in electrolyte.…”

Review of Antibacterial Activity of Titanium-based Implants Surfaces Fabricated by Micro-arc Oxidation

“…Meanwhile, the osteoblastic adhesion, spreading, early proliferation and late differentiation on Cu-TiO2 coatings were significantly enhanced due to the existence of the porous nano-structured surface produced during MAO, just like those found by other researchers [81,94]. Besides, Cu element also plays a vital role in various cell behavior, including osteoblasts [95], endothelial cells [96], bone marrow stem cells [63] and fibroblasts [64]. Zhang et al [64] have investigated the tolerable and safe upper intake level of Cu 2+ in order to improve the response of fibroblasts while maintaining the antibacterial activity.…”

Multifunctional coatings to simultaneously promote osseointegration and prevent infection of orthopaedic implants

“…Additionally, the Zn inhibited S. aureus growth, with longer-term bactericidal activity expected given the slow release of ions over one month. Other modification strategies have included the incorporation of silver [89] and copper [90] into nanotubes to serve as bactericidal agents, again taking advantage of the high surface area and loading capacity of nanotubes.…”