Herbert Gleiter Institute of Nanoscience , Nanjing University of Science and Technology , Nanjing 210094 , P. R. China.
State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering , Southeast University , Nanjing 210096 , P. R. China.
Langmuir. 2019 Feb 19;35(7):2480-2489. doi: 10.1021/acs.langmuir.8b02796. Epub 2019 Feb 6.
The design of topographically patterned surfaces is considered to be a preferable approach for influencing cellular behavior in a controllable manner, in particular to improve the osteogenic ability of bone regeneration. In this study, we fabricated nanolamellar tantalum (Ta) surfaces with lamellar wall thicknesses of 40 and 70 nm. The cells attached to nanolamellar Ta surfaces exhibited higher protein adsorption and expression of β1 integrin, as compared to the nonstructured bulk Ta, which facilitated the initial cell attachment and spreading. We thus, as expected, observed significantly enhanced osteoblast adhesion, growth, and alkaline phosphatase activity on nanolamellar Ta surfaces. However, the beneficial effects of nanolamellar structures on osteogenesis became weaker as the lamellar wall thickness increased. The interaction between cells and Ta surfaces was examined through adhesion forces using atomic force microscopy. Our findings indicated that the Ta surface with a lamellar wall thickness of 40 nm exhibited the strongest stimulatory effect. The observed strongest adhesion force between the cell-attached tip and the Ta surface with a 40 nm thick lamellar wall encouraged the much stronger binding of cells with the surface and thus well-attached, -stretched, and -grown cells. We attributed this to the increase in the available contact area of cells with the thinner nanolamellar Ta surface. The increased contact area allowed the enhancement of the cell surface interaction strength and, thus, improved osteoblast adhesion. This study suggests that the thin nanolamellar topography shows immense potential in improving the clinical performance of dental and orthopedic implants.
具有纳米层状结构的钽表面的制备，其层状壁厚度分别为 40nm 和 70nm。与非纳米结构的体钽相比，附着在纳米层状钽表面的细胞表现出更高的蛋白质吸附和β1 整合素表达，从而促进了初始细胞附着和扩展。因此，正如预期的那样，我们观察到纳米层状 Ta 表面上成骨细胞的黏附、生长和碱性磷酸酶活性显著增强。然而，随着层状壁厚度的增加，纳米层状结构对成骨的有益影响变得较弱。通过原子力显微镜的粘附力研究了细胞与 Ta 表面的相互作用。研究结果表明，层状壁厚度为 40nm 的 Ta 表面表现出最强的刺激作用。在具有 40nm 厚层状壁的 Ta 表面上，附着的细胞尖端之间的观察到最强的粘附力，这鼓励了细胞与表面更强的结合，从而使细胞能够很好地附着、伸展和生长。我们将其归因于细胞与更薄的纳米层状 Ta 表面的可用接触面积增加。增加的接触面积允许增强细胞表面相互作用强度，从而改善成骨细胞的黏附。本研究表明，薄纳米层状形貌在改善牙科和骨科植入物的临床性能方面具有巨大潜力。
