Popat Ketul C, Daniels R Hugh, Dubrow Robert S, Hardev Veeral, Desai Tejal A
Department of Physiology, University of California at San Francisco, Room QB3-203C, Box 2520, Mission Bay Campus, 1700 4th Street, San Francisco, California 94143-2520, USA.
J Orthop Res. 2006 Apr;24(4):619-27. doi: 10.1002/jor.20105.
A major goal of orthopedic biomaterials research is to design better surface chemistries and configurations to control behavior of bone cells such as osteoblasts. Nanostructured architecture significantly affects the response of several cell lines. In this work, nanostructured surfaces were prepared by vapor liquid solid growth of silicon nanowires from size-controlled gold colloid catalysts deposited on fused silica substrates. The lengths and surface densities of the nanowires were varied to assess the effect of these parameters on bone cell response. Osteoblasts were seeded on nanowire surfaces to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assay and cell counting for up to 4 days of culture. The total protein content, alkaline phosphatase activity, and matrix production were quantified using standard colorimetric assays for up to 4 weeks of culture. Matrix production was also characterized by measuring surface concentrations of calcium and phosphorus using X-ray photoelectron spectroscopy. Further, scanning electron microscopy was used to investigate osteoblast morphology on nanostructured surfaces. Over the 4-week study, the nanostructured surfaces demonstrated improved osteoblast adhesion and proliferation and increased alkaline phosphatase activity and matrix production compared to non-nanostructured control surfaces.
骨科生物材料研究的一个主要目标是设计出更好的表面化学性质和结构，以控制骨细胞（如成骨细胞）的行为。纳米结构显著影响多种细胞系的反应。在这项工作中，通过气液固生长法，以沉积在熔融石英基底上的尺寸可控的金胶体催化剂制备硅纳米线，从而制备出纳米结构表面。改变纳米线的长度和表面密度，以评估这些参数对骨细胞反应的影响。将成骨细胞接种在纳米线表面，研究其短期黏附与增殖以及长期功能和基质生成情况。使用标准的3-[4,5-二甲基噻唑-2-基]-2,5-二苯基溴化四氮唑法和细胞计数对细胞黏附与增殖进行表征，培养时间长达4天。使用标准比色法对培养长达4周的总蛋白含量、碱性磷酸酶活性和基质生成进行定量。还通过X射线光电子能谱测量钙和磷的表面浓度来表征基质生成情况。此外，使用扫描电子显微镜研究纳米结构表面上的成骨细胞形态。在为期4周的研究中，与非纳米结构的对照表面相比，纳米结构表面显示出更好的成骨细胞黏附与增殖，以及更高的碱性磷酸酶活性和基质生成。
