Jiang Pinliang, Zhang Yanmei, Hu Ren, Wang Xiankuan, Lai Yuekun, Rui Gang, Lin Changjian
College of Materials, Xiamen University, Xiamen, 361005, China.
State Key Lab of Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
Bioact Mater. 2020 Oct 20;6(4):1118-1129. doi: 10.1016/j.bioactmat.2020.10.006. eCollection 2021 Apr.
Surface structures and physicochemical properties critically influence osseointegration of titanium (Ti) implants. Previous studies have shown that the surface with both micro- and nanoscale roughness may provide multiple features comparable to cell dimensions and thus efficiently regulate cell-material interaction. However, less attention has been made to further optimize the physicochemical properties (e.g., crystalline phase) and to further improve the bioactivity of micro/nanostructured surfaces. Herein, micro/nanostructured titania surfaces with different crystalline phases (amorphous, anatase and anatase/rutile) were prepared and hydroxyapatite (HA) nanorods were deposited onto the as-prepared surfaces by a spin-assisted layer-by-layer assembly method without greatly altering the initial multi-scale morphology and wettability. The effects of crystalline phase, chemical composition and wettability on osteoblast response were investigated. It is noted that all the micro/nanostructured surfaces with/without HA modification presented superamphiphilic. The activities of MC3T3-E1 cells suggested that the proliferation trend on the micro/nanostructured surfaces was greatly influenced by different crystalline phases, and the highest proliferation rate was obtained on the anatase/rutile surface, followed by the anatase; but the cell differentiation and extracellular matrix mineralization were almost the same among them. After ultrathin HA modification on the micro/nanostructured surfaces with different crystalline phases, it exhibited similar proliferation trend as the original surfaces; however, the cell differentiation and extracellular matrix mineralization were significantly improved. The results indicate that the introduction of ultrathin HA to the micro/nanostructured surfaces with optimized crystalline phase benefits cell proliferation, differentiation and maturation, which suggests a favorable biomimetic microenvironment and provides the potential for enhanced implant osseointegration in vivo.
表面结构和物理化学性质对钛（Ti）植入物的骨整合有着至关重要的影响。先前的研究表明，具有微米和纳米尺度粗糙度的表面可能提供与细胞尺寸相当的多种特征，从而有效地调节细胞与材料的相互作用。然而，对于进一步优化物理化学性质（如晶相）以及进一步提高微/纳米结构表面的生物活性，人们关注较少。在此，制备了具有不同晶相（非晶态、锐钛矿型和锐钛矿/金红石型）的微/纳米结构二氧化钛表面，并通过旋转辅助逐层组装方法将羟基磷灰石（HA）纳米棒沉积在制备好的表面上，而不会显著改变初始的多尺度形态和润湿性。研究了晶相、化学成分和润湿性对成骨细胞反应的影响。值得注意的是，所有经过/未经过HA修饰的微/纳米结构表面均呈现超双亲性。MC3T3-E1细胞的活性表明，微/纳米结构表面上的增殖趋势受不同晶相的显著影响，在锐钛矿/金红石型表面上获得最高增殖率，其次是锐钛矿型；但它们之间的细胞分化和细胞外基质矿化几乎相同。在不同晶相的微/纳米结构表面进行超薄HA修饰后，其增殖趋势与原始表面相似；然而，细胞分化和细胞外基质矿化得到显著改善。结果表明，将超薄HA引入具有优化晶相的微/纳米结构表面有利于细胞增殖、分化和成熟，这表明了一个良好的仿生微环境，并为体内增强植入物的骨整合提供了潜力。
