Study The Cytocompatibility Of Fluorine-contained Polymer Film Modified Ti-6Al-4V

Titanium alloy, mainly containing Ti-6A1-4V and having good physical and chemical properties, mechanical processing performance and biocompatibility characteristics, thus has been widely used as a surgical implant material in clinical work. Studies have shown that the Ti-6A1-4V alloy has good corrosion resistance because it can generate a stable TiO2film under normal condition. However, the TiO2films may be dissolved and even exfoliated because of its limited stability in the complex environment of human body fluids. The precipitation of potential toxic elements in titanium alloys, such as A1and V, also could induce toxic effecty, inflammation, thrombosis and other negative reactions. Moreover, the implanted alloy might not be able to form satisfied osseointegration beause it has no obvious role in promoting healing as lack of the biological activity. So it is neccesary to modify the surface of the Ti-6A1-4V alloy to improve the corrosion resistance and biocompatibility.In this study, We applied the fluorine-containing polymer material which was synthesized in our research group, i.e.4-vinyl benzocyclobutene and2,3,4,5,6-pentafluoro-styrene random copolymer (P(PFSt-r-4-VBCB)), which were used to prepare the fluorine-containing polymer film on the Ti-6A1-4V alloy surface by the method of spin coating and thermal crosslinking. This film could provide effective protection and improve osteogenesis potential and cytocompatibility of Ti-6A1-4V alloy. This paper examined the corrosion resistance of Ti-6A1-4V alloy surface preparation of the fluorine-contained polymer thin films before and after in simulated body fluid (SBF), artificial saliva (AS) and0.9%sodium chloride solution;the cytotoxic of modified Ti-6A1-4V alloy was investigated by in vitro cell study; and the celluar influence was evaluated with the effect of osteoblasts by investigating cell adhesion, cell proliferation, cell differentiation and cell cycle in on the Ti-6A1-4V alloy modification; the fluorescence microscopy and scanning electron microscopy were used to observe the adhesion and cell morphology of osteoblastsThe results of this study had shown that:1). The electrochemical corrosion results showed the corrosion current density of Ti-6A1-4V alloy with fluoro polymer film were significantly lower than the unmodified one respectively in simulated body fluid, artificial saliva and0.9%sodium chloride solution.2). In vitro cytotoxicity tests showed the cells relative growth rate (RGR) of Ti-6A1-4V alloy coated on fluoropolymer film were higher than a hundred percent, and the level of cytotoxicity rating was0after cells were seeded after2,4days.3). In vitro osteoblasts results suggested the fluorine-contained polymer thin films could promote the transformation of osteoblasts from G0/G1phase to S phase, in order to facilitate DNA synthesis and cell proliferation; and improve the secretion of alkaline phosphatase (ALP) and synthetsis of bone calcium protein (BGP).According to the above experimental results, we conclude that the fluorine-contained polymer thin films could provide effective protection to the substrate of Ti-6A1-4V alloy and improve biocompatibility of osteoblasts, and it has benefit to potential application value in the biomedical.