Biomedical Engineering Institute, South China University of Technology, Guangzhou, People's Republic of China.
J Biomed Mater Res A. 2010 Sep 15;94(4):1091-9. doi: 10.1002/jbm.a.32776.
Bioactive glasses (BGs) have been widely used for bone tissue regeneration as they are able to bond directly with bone. Clinical applications of these materials are likely to be in particulate form. Nanoscale materials can mimic the surface properties of natural tissues, which have exhibited superior cytocompatible property and improved tissue regeneration. The objective of this study is to prepare bioactive glass particles with nanoscale or non-nanoscale surface features and investigate their microstructure, apatite-forming bioactivity and cellular response. The microstructure and micro-nanoscale surface morphology were controlled by adding a hydroxyl-carboxyl acid (citric acid) in the sol-gel process. Results shown that the addition of citric acid induced the formation of nanoscale surface structure and increased the specific surface area, pore volume and pore size of bioactive glass particles. The citric acid with low-concentration-derived sol-gel bioactive glasses (CBGs) resulted in an enhanced apatite-formation ability in simulated body fluids (SBF) compared to normal bioactive glasses. The attachment and proliferation of rat marrow mesenchymal stem cells (RMSCs) on CBGs (low concentration) were higher than those of normal BGs, demonstrating that the CBGs had the excellent cytocompatibility. RMSCs on CBGs (low concentration) expressed the higher alkaline phosphatase activity (ALP) than normal BGs and tissue culture plastic, revealing that CBGs can induced differentiation of RMSCs to the osteogenic lineage. Such improved physical and biological properties of CBGs (low concentration) should be useful in developing new bioactive glass materials for stem cell-based bone regeneration or biomimic tissue engineering scaffolds.
生物活性玻璃（BGs）因其能够与骨骼直接结合而被广泛用于骨组织再生。这些材料的临床应用可能是颗粒状的。纳米级材料可以模拟天然组织的表面特性，具有优异的细胞相容性和改善组织再生的特性。本研究的目的是制备具有纳米级或非纳米级表面特征的生物活性玻璃颗粒，并研究其微观结构、磷灰石形成的生物活性和细胞反应。通过在溶胶-凝胶过程中添加羟基-羧酸（柠檬酸）来控制微观结构和微纳米级表面形态。结果表明，柠檬酸的添加诱导了纳米级表面结构的形成，并增加了生物活性玻璃颗粒的比表面积、孔体积和孔径。与普通生物活性玻璃相比，柠檬酸低浓度衍生溶胶-凝胶生物活性玻璃（CBGs）在模拟体液（SBF）中表现出更强的磷灰石形成能力。在 CBGs（低浓度）上，大鼠骨髓间充质干细胞（RMSCs）的附着和增殖高于普通 BGs，表明 CBGs 具有良好的细胞相容性。在 CBGs（低浓度）上的 RMSCs 表达的碱性磷酸酶活性（ALP）高于普通 BGs 和组织培养塑料，表明 CBGs 可以诱导 RMSCs 向成骨细胞系分化。CBGs（低浓度）的这些改善的物理和生物学特性对于开发基于干细胞的骨再生或仿生组织工程支架的新型生物活性玻璃材料将是有用的。
