Anodic Oxidation Modification Improve Bioactivity and Biocompatibility of Titanium Implant Surface

Development of Titania Nanotube-based Electrochemical Immunosensor and Determination of Prostate Specific Antigen

Early diagnosis of cancer is the most important factor that increases the success of treatment. Therefore, the development of new diagnostic tools is a necessity. In this study, a new electrode surface was developed via modification of a disposable titanium electrode with anodic oxidation and coating of gold nanoparticle and chitosan. Titanium electrodes were anodized by several anodization parameters to obtain a nanoporous surface and characterized by scanning electron microscopy. Electrodes anodized in optimum conditions were modified with gold nanoparticles and chitosan for enhancing conductivity and functionalizing the surface of electrode, respectively. To detect prostate specific antigen (PSA), anti-PSA was bound onto the functional electrode surface. Modified electrodes were characterized with scanning electron microscopy and cyclic voltammetry and used for chronoamperometric detection of PSA. Limit of detection (LOD) of the designed electrode was found to be 7.8 ng mL^-1 for PSA in a linear range of 0 - 100 ng mL^-1.

Biological and Mechanical Effects of Micro-Nanostructured Titanium Surface on an Osteoblastic Cell Line In vitro and Osteointegration In vivo

Hybrid micro-nanostructure implant surface was produced on titanium (Ti) surface by acid etching and anodic oxidation to improve the biological and mechanical properties. The biological properties of the micro-nanostructure were investigated by simulated body fluid (SBF) soaking test and MC3T3-E1 cell co-culture experiment. The cell proliferation, spreading, and bone sialoprotein (BSP) gene expression were examined by MTT, SEM, and reverse transcription-polymerase chain reaction (RT-PCR), respectively. In addition, the mechanical properties were evaluated by instrumented nanoindentation test and friction-wear test. Furthermore, the effect of the micro-nanostructure surface on implant osteointegration was examined by in vivo experiment. The results showed that the formation of bone-like apatite was accelerated on the micro-nanostructured Ti surface after immersion in simulated body fluid, and the proliferation, spreading, and BSP gene expression of the MC3T3-E1 cells were also upregulated on the modified surface. The micro-nanostructured Ti surface displayed decreased friction coefficient, stiffness value, and Young's modulus which were much closer to those of the cortical bone, compared to the polished Ti surface. This suggested much better mechanical match to the surrounding bone tissue of the micro-nanostructured Ti surface. Furthermore, the in vivo animal experiment showed that after implantation in the rat femora, the micro-nanostructure surface displayed higher bonding strength between bone tissues and implant; hematoxylin and eosin (H&E) staining suggested that much compact osteoid tissue was observed at the interface of Micro-nano-Ti-bone than polished Ti-bone interface after implantation. Based on these results mentioned above, it was concluded that the improved biological and mechanical properties of the micro-nanostructure endowed Ti surface with good biocompatibility and better osteointegration, implying the enlarged application of the micro-nanostructure surface Ti implants in future.

Corrosion resistance and biological properties of a micro–nano structured Ti surface consisting of TiO2 and hydroxyapatite

A micro–nanostructured Ti surface consisting of TiO₂ and HA was prepared by MAO, and showed improved corrosion resistance and biological properties.

Improvement of biological and mechanical properties of titanium surface by anodic oxidation

A homogeneous and uniform array of nanotubes with a diameter of about 70 nm was produced on titanium (Ti) surface by anodic oxidation. The wall thickness of the nanotubes was around 20 nm, and the depth was about 200 nm. The biological properties of the anodized Ti surface were investigated by simulated body fluid (SBF) soaking test and in vitro cell culture test. The mechanical properties were evaluated by instrumented nanoindentation test and friction-wear test. The results showed that the anodized Ti surface can induce the formation of bone-like apatite after immersion in SBF for four weeks, enhance cell adhesion, proliferation and gene expression, it also showed decreased friction coefficient, similar stiffness and Young's modulus to those of the cortical bone. Based on these results, it can be concluded that anodic oxidation endowed the Ti surface with improved biological and mechanical properties, which was attributed to the formation of nanostructured surface.

Synergistic effects of hierarchical hybrid micro/nanostructures on the biological properties of titanium orthopaedic implants

Hybrid micro/nanotopographic features are of crucial importance to the activity of osteoblasts.