The Effects of Micro- and Nano-structured Biomaterial Surfaces on Osteogenetic-Related Cells
(PDF)The Effects of Micro- and Nano-structured Biomaterial Surfaces on Osteogenetic-Related Cells
(1 Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University,Chengdu 610031, China)
(2 Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China)
Surface properties including topography and chemistry are of great significance in deciding the response of tissue 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-structures. 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 micromachining technology; Chitosan /bovine serum albumin micropatterns were prepared on functionalized Ti surfaces by micro-transfer molding combined with self-assembly. For nanostructures, titania nanotubes with various diameters and lengths were prepared by a electrochemical anodic oxidation treatment. For micro-nano hierarchical structures, titania micropores modified with nanotubes were obtained by high voltage micro-arc oxidation and low voltage anodization. In addition to consider the effects of micro-nano structure alone, the synergistic effects of struturalization and biofunctionalization of biomaterial 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 results 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 nanodots, 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 micro/nano structures and biofuctionalization 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.