Electrically bioactive coating on Ti with bi-layered SnO₂–TiO₂ hetero-structure for improving osteointegration

Abstract

SnO2–TiO2 surface with the bi-layered structure on Ti provides internal electric stimulation to promote osteointegration of implant.

Construction of ZnO/SnO2 Heterostructure on Reduced Graphene Oxide for Enhanced Nitrogen Dioxide Sensitive Performances at Room Temperature

“…25,26 Additionally, the distribution of carriers and oxygen vacancies at the interface of heterojunctions can be regulated by the band structure of the semiconductor and can further influence gas sensing properties. 27 However, the sensors based on p-n heterostructure nanomaterials are unreliable and unstable because of the weak contact between the two types of materials, which tend to form homotypic heterojunctions. 23 There are few free electrons in the depletion regions formed at the interface of pn junctions due to electron−hole recombination.…”

Enhanced Osseointegration of Hierarchically Structured Ti Implant with Electrically Bioactive SnO2–TiO2 Bilayered Surface

“…UV-vis absorption spectra of Ti-TiO 2 , Ti-SnO 2 , and Ti-TiO 2 -SnO 2 , b) LSV curves of Ti-TiO 2 , and Ti-TiO 2 -SnO 2 , c) schematic diagram for the built-in electrical field of SnO 2 -TiO 2 heterojunction, and the plots of (αhν) 2 versus hν of d) Ti-TiO 2 , e) Ti-SnO 2 , f) Ti-TiO 2 -SnO 2 .Due to the similar phase composition and structure of the bi-layered SnO 2 -TiO 2 coating with our previous work on Ti plate,30 an n-n heterojunction could be formed on the R-Ti-TiO 2 -SnO 2 surface. To confirm the formation of the SnO 2 -TiO 2 heterojunction, the band gap of the SnO 2 -TiO 2 coating has been determined by UV-vis spectrophotometer using Ultra Violet Diffuse Reflectance Spectroscopy technique (Figure 4).…”

“…[32][33][34] The amorphous MAO coating with SnO 2 film cannot form a heterojunction with electrically stimulated bioactivity because it cannot obtain a stable Fermi energy of TiO 2 to promote the separation of hole-electron pairs. 30 To meet the formation requirement of heterojunction with type II aligned structure, 35,36 revealing that the gouge does not affect the phase composition of MAO coating (Figure 2(b)).…”

“…29 Interestingly, a built-in electrical field on smooth Ti plate via the formation of bi-layered SnO 2 -TiO 2 heterojunction with type II band alignment was reported in our previous work, which exhibited superhydrophilicity and good apatite-forming ability. 30 To render the hierarchically porous Ti implant with excellent bioactivity, in this work, the bi-layered SnO 2 -TiO 2 heterojunction was fabricated on the surface of hierarchically structured Ti implant by MAO and subsequent hydrothermal treatment.…”

“…Though the Ti-TiO 2 -SnO 2 shows similar surface roughness with Ti-TiO 2 , the equilibrium of BMUs around it shifts significantly towards the generation of new bone. This phoneme is obviously dominated by the electrical bioactivity of the bi-layered coating rather than the nano-topography of the SnO 2 surface, as the densely packed SnO 2 nanorods would not benefit focal adhesion assembly of cells 30,53,54. Specifically, transient receptor potential melastatin (TRPM7) protein is one of the signaling pathways on plasma membranes, exhibiting spontaneously activated divalent cation (Ca 2+ , Mg 2+ ) entry, which is important for osteoblast differentiation 55,56.…”