纳米羟基磷灰石/大管径TiO2纳米管复合涂层促成骨

摘要

背景:羟基磷灰石和大管径TiO2纳米管均被证实具有良好的生物活性,但目前缺乏在大管径TiO2纳米管表面沉积纳米羟基磷灰石促成骨方面的研究.目的:检测纳米羟基磷灰石/大管径TiO2纳米管复合涂层的促成骨能力.方法:采用阳极氧化法制备大管径TiO2纳米管,电化学法于纳米管表面沉积纳米羟基磷灰石.将MC3T3-E1前成骨细胞分别与纳米羟基磷灰石/大管径TiO2纳米管复合涂层、纯钛及大管径TiO2纳米管涂层共培养,培养0.5,1,2 h,观察细胞初始黏附;培养1,3,5 d后,检测细胞增殖;培养2 d后,观察细胞形态;成骨诱导培养3,7 d后,检测细胞碱性磷酸酶活力;成骨诱导培养14 d后,检测细胞外基质矿化能力.结果与结论:①培养2 h时,TiO2纳米管组细胞数高于纳米羟基磷灰石/大管径TiO2纳米管组(P<0.05),纳米羟基磷灰石/大管径TiO2纳米管组与纯钛组比较差异无显著性意义;②培养1,3,5 d时,TiO2纳米管组细胞增殖数量高于纳米羟基磷灰石/大管径TiO2纳米管组、纯钛组(P<0.05),纳米羟基磷灰石/大管径TiO2纳米管组与纯钛组比较差异无显著性意义;③纯钛上的细胞呈梭形;TiO2纳米管涂层上的细胞有丝状伪足伸出;纳米羟基磷灰石/大管径TiO2纳米管复合涂层上的细胞呈多边形,伸出的伪足数量更多;④纳米羟基磷灰石/大管径TiO2纳米管组细胞内碱性磷酸酶活性、细胞外基质矿化程度明显高于TiO2纳米管组、纯钛组;⑤结果表明,纳米羟基磷灰石/大管径TiO2纳米管复合涂层不仅具有良好的生物相容性,而且具有理想的促成骨能力.%BACKGROUND: Both hydroxyapatite (HA) and large diameter TiO2 nanotubes have excellent biocompatibility, but bone-forming ability of nano-HA (nHA) deposited large diameter TiO2 nanotubes is rarely reported.OBJECTIVE: To evaluate the bone-forming ability of nHA/large-diameter TiO2 nanotube composite coating.METHODS: Large-diameter TiO2 nanotubes were prepared by anodic oxidation method, and then nHA was electrochemically deposited on the surface of TiO2 nanotubes. Preosteoblasts MC3T3-E1 were co-cultured with the nHA/large diameter TiO2 nanotube composite, pure titanium and TiO2 nanotube coatings, respectively. At 0.5, 1, 2 hours after culture, the initial cell adhesion was observed. At 1, 3, 5 day after culture, cell proliferation was assessed. At 2 days after culture, cell morphology was observed. At 3 and 7 days after osteogenic induction, intracellular alkaline phosphatase activity was detected. At 14 days after osteogenic induction, mineralization of extracellular matrix was detected.RESULTS AND CONCLUSION: (1) After 2 hours of culture, the number of adherent cells on the composite coating was significantly lower than that on the TiO2 nanotube coating (P < 0.05), but slightly higher than that on the pure titanium coating with no statistical difference. (2) After 1, 3, 5 days of culture, the cell proliferation on the composite coating was significantly lower than that on the TiO2 nanotube coating (P < 0.05), but slightly higher than that on the pure titanium with no statistical difference. (3) The cells on the pure titanium showed a spindle-shape, while those on the TiO2 nanotube coating processed filopodia. The cells on the composite coating showed polygonal shape with a larger number of filopodia. (4) The intracellular alkaline phosphatase activity of the composite coating group was significantly higher than that of the pure titanium group and TiO2 nanotube group. The trend of mineralization of extracellular matrix was ranked from high to low: the composite coating group > TiO2 nanotube group > pure titanium group. To conclude, the nHA/large diameter TiO2 nanotube composite coating not only has good biocompatibility, but also has the ideal ability to promote bone formation.