The Construction Of Functional Nanocomposite Multilayer Films On Titanium Surface And Its Effect On Osseogenesis In Vivo

Titanium and its alloys are common metal materials. Due to its good biocompatibility and mechanical properties, they are widely used in bone tissue repair engineering, artificial joints, dental implants and other fields. However, as implanted bone repair material,titanium can’t integrated with surrounding bone tissue because of its inert property when it was implanted into the host,leading to the failure of implantation. The combination time of titanium implants with nature bone tissue not only depends on surface topology structure and chemical properties, but also on the influence of implant surrounding bone mass and bone mineral density. At present, our country has 50 million patients with osteoporosis, which is characterized with the reducementof bone mass and bone mineral density, resulting in frequency of fracture and difficulty operation. It was also the main reason that leads to the implants loose and finall failure of surgical in patient with osteoporosis.In this study, a natural polysaccharides-derived nanocomposite containing alendronate-grafted hyaluronate(HA-Aln) and bone morphogenetic protein 2(BMP-2) was embedded into the multilayer network of titanium alloy surface. First of all, HA-Aln molecule synthesized by acetylation was characterized by FTIR and 1 HNMR. HA-Aln/BMP-2 nanocomposite was then prepared via electrostatic interaction. The morphology, load-drug activity and bone targeted feature of those nanocomposites were investegated. Meanwhile, we explored the interaction between the nanocomposites and osteoblasts or osteoclasts in vitro, including the morphology observtion, migration property and bone-related gene expression of osteoblasts as well as the inhibition effect of osteoclasts differentation. Finally, functional nanoparticles inserted layer structure on the surface of titanium alloy was constructed via the layer-by-layer assembly technique and then characterized whit CLSM, SEM and the contact angle measurement.The results of X-ray scanning,push-out testing and Micro-CT analysis showed that functional multilayer films modified titanium alloyswas able to improve the implant integration with surrounding bone tissue in vivo. It laid the groundwork for the development of novel titanium implant and related technique.