It has been revealed that the different morphologies of anodized TiO2 nanotubes, especially nanotube diameters, triggered different cell behaviors. However, the influence of TiO2 nanotubes with coexisting multi-size diameters on cell behaviors is seldom reported. In this work, coexisting four-diameter TiO2 nanotube samples, namely, one single substrate with the integration of four different nanotube diameters (60, 150, 250, and 350 nm), were prepared by repeated anodization. The boundaries between two different diameter regions show well-organized structure without obvious difference in height. The adhesion behaviors of MC3T3-E1 cells on the coexisting four-diameter TiO2 nanotube arrays were investigated. The results exhibit a significant difference of cell density between smaller diameters (60 and 150 nm) and larger diameters (250 and 350 nm) within 24 h incubation with the coexistence of different diameters, which is totally different from that on the single-diameter TiO2 nanotube arrays. The coexistence of four different diameters does not change greatly the cell morphologies compared with the single-diameter nanotubes. The findings in this work are expected to offer further understanding of the interaction between cells and materials.

中文翻译：

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共存多种尺寸直径的阳极氧化TiO2纳米管阵列上细胞行为的研究。

已经发现，阳极氧化的TiO2纳米管的不同形态，特别是纳米管的直径，触发了不同的电池行为。然而，很少有多种直径的TiO2纳米管并存对细胞行为的影响。在这项工作中，通过重复阳极氧化制备共存的四直径TiO2纳米管样品，即集成了四个不同纳米管直径（60、150、250和350 nm）的单个基板。两个不同直径区域之间的边界显示出组织良好的结构，高度没有明显差异。研究了MC3T3-E1细胞在并存的四直径TiO2纳米管阵列上的粘附行为。结果显示，在孵育24小时后，较小直径（60和150 nm）和较大直径（250和350 nm）之间的细胞密度存在显着差异，并且共存不同直径，这与单直径TiO2完全不同纳米管阵列。与单直径纳米管相比，四种不同直径的共存不会显着改变细胞形态。这项工作中的发现有望提供对细胞与材料之间相互作用的进一步理解。