Wu Jialing, Huang Jingyan, Yun Jiaojiao, Yang Jiajun, Yang Jinghong, Fok Alex, Wang Yan
Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055, China.
Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, Minnesota 55455, United States.
ACS Biomater Sci Eng. 2019 Jun 10;5(6):2769-2777. doi: 10.1021/acsbiomaterials.9b00418. Epub 2019 May 29.
Hydroxyapatite (HA)-coated TiO nanotubes (TNTs) have been reported to enhance osteogenesis. However, the nanoscale topography of TNTs usually vanishes due to the uncontrollable mineralization on the surface. In this study, TNTs with different diameters(small, 25 nm; medium, 55 nm; and large, 85 nm) were fabricated by anodization in 3 different voltages. Enzyme-directed biomineralization was adopted to deposit calcium phosphate on the above TNTs. The surface structures and properties of the coatings were characterized by scanning electron microscopy, dispersive X-ray spectrometry, X-ray diffraction, and Fourier-transform infrared spectroscopy. The osteogenesis effect of the hybrid TNT/HA and the original TNTs were evaluated. The results showed that hydroxyapatite deposited homogeneously along the TiO nanotubes while preserving the intrinsic nanotopography. Mechanically, alkaline phosphatase(ALP) played a critical role in the mineralization and large nanotube size is more favorable for the mineralizing process because of more ALP absorption. Besides, the hybrid nanosurface TNT/HA coating was found to improve the adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells compared to pure TNTs. Our study suggests that the hybrid TNT/HA coating constructed by enzyme-directed biomineralization on TiO nanotubes is a promising modification strategy for titanium implants.
据报道，羟基磷灰石（HA）涂层的二氧化钛纳米管（TNTs）可增强成骨作用。然而，由于表面矿化不可控，TNTs的纳米级形貌通常会消失。在本研究中，通过在3种不同电压下进行阳极氧化制备了不同直径（小，25nm；中，55nm；大，85nm）的TNTs。采用酶促生物矿化法在上述TNTs上沉积磷酸钙。通过扫描电子显微镜、色散X射线光谱、X射线衍射和傅里叶变换红外光谱对涂层的表面结构和性能进行了表征。评估了TNT/HA复合材料和原始TNTs的成骨效果。结果表明，羟基磷灰石沿TiO纳米管均匀沉积，同时保留了固有的纳米形貌。从力学角度来看，碱性磷酸酶（ALP）在矿化过程中起关键作用，大尺寸纳米管更有利于矿化过程，因为其能吸收更多的ALP。此外，与纯TNTs相比，发现TNT/HA复合纳米表面涂层可改善MC3T3-E1细胞的黏附、增殖和成骨分化。我们的研究表明，通过酶促生物矿化在TiO纳米管上构建的TNT/HA复合涂层是一种很有前景的钛植入物改性策略。
