生物材料表面微纳结构对成骨相关细胞的影响

生物医用材料表面性能，包括表面形貌与化学组成，对诱导骨组织形成并形成骨整合具有重要作用。细胞行为对基底表面形貌和组成的依赖性决定了设计不同功能表面的重要性。作者小组多年来从事生物材料表面微纳结构相关研究。在微图形方面，结合微加工和磁控溅射技术制备出的羟基磷灰石微沟槽；采用溶胶一凝胶与复制微模塑相结合的方法制备了TiO2微图形；采用掩模曝光电化学微加工技术和喷射电化学微加工技术，在钛基底上制备多孔微图形；通过转移微模塑法与自组装技术相结合，得到壳聚糖与牛血清蛋白复合微图形。在纳米结构方面，采用电化学阳极氧化处理，获得一定管径和管长的二氧化钛纳米管。在微纳多级结构方面，结合高压微弧氧化和低压阳极氧化制备了微纳多级结构钛表面。除了考虑微纳结构单独效应之外，还考虑了微纳结构化与生物功能化的协同效应，即在具有微纳结构的生物材料表面通过层层自组装等手段进行生物化学修饰。最后通过成骨相关细胞培养实验及体内植入实验，考察各试样的生物活性。研究表明，微米尺度表面促进骨细胞粘附、增殖、分化等，而纳米尺寸结构以及微纳多级结构对细胞功能具有进一步促进作用。微纳结构化与表面功能化修饰存在有协同效应。这些研究结果为微纳米技术应用于人体植入研究提供了新方向。

The Effects of Micro- and Nano-Structured Biomaterial Surfaces on Osteogenetic-Related Cells

Surface properties including topography and chemistry are of great significance in deciding the response of tis- sue to implants. Our group has been engaged in researches on micro/nano structured biomaterial surfaces for a long time. This article reviews our series works on osteogenetic cells behavior on biomaterial surfaces with micro-and nano-struetures. For micro-patterns, hydroxyapatite microgrooves were prepared by combining micro-fabrication technology and magnetron sputtering technology; TiO2 micropatterns were obtained by combining sol-gel and replica molding; Micro-patterned Ti substrates were prepared by using a through mask electrochemical micromachining and a jet electrochemical micromachin- ing technology; chitosan/bovine serum albumin micropatterus were prepared on functionalized Ti surfaces by micro-trans- fer molding combined with self-assembly. For nanostruetures, titania nanotubes with various diameters and lengths were prepared by a electrochemical anodic oxidation treatment. For micro-nano hierarchical structures, titania micropores modi- fied with nanotubes were obtained by high voltage micro-arc oxidation and low voltage anodization. In addition to consider- ing the effects of micro-nano structure alone, the synergistic effects of struturalization and biofunctionalization of biomateri-al surfaces were investigated, which were realized through layer-by-layer self-assembly and other means of biochemical modification on micro/nano structured surfaces. Finally, in vitro osteogenetic cell culture and in vivo study were conducted to investigate the biological activity of various sample. The re- suits indicate that micro-scale topographical features promote cell adhesion, bone ingrowth and the formation of mechanical interlocking between the implant surfaces and bone tissue. The nano-scale features, including nanotubes, nanofibers and nan- odots, can generate preferential interactions with a biological system at protein and cellular levels, such as cell proliferation,differentiation, and gene expression. The micro/nano hierarchical surface structures further enhance cell activity. The mi- cro/nano structures amt biothctionalization with biomolecules and biofilms have synergistic effects on cell behaviors. These studies provide a potential new direction for the application of micro/nano technology on implant surface modification.