Department of Mechanical Engineering, University College London, London WC1E 7JE, UK.
Biomaterials, Tissue Engineering & Imaging, The Dental Institute, King's College London, Guy's Hospital, London SE1 9BT, UK.
Mater Sci Eng C Mater Biol Appl. 2014 Mar 1;36:206-14. doi: 10.1016/j.msec.2013.12.009. Epub 2013 Dec 15.
A multi-step sol-gel process was employed to synthesize bioactive glass (BG) nanoparticles. Transmission electron microscopy (TEM) revealed that the BG nanoparticles were spherical and ranged from 30 to 60 nm in diameter. In vitro reactivity of the BG nanoparticles was tested in phosphate buffer saline (PBS), Tris-buffer (TRIS), simulated body fluid (SBF), and Dulbecco's modified Eagle's medium (DMEM), in comparison with similar sized hydroxyapatite (HA) and silicon substituted HA (SiHA) nanoparticles. Bioactivity of the BG nanoparticles was confirmed through Fourier transform infrared spectroscopy (FTIR) analysis. It was found that bone-like apatite was formed after immersion in SBF at 7 days. Solutions containing BG nanoparticles were slightly more alkaline than HA and SiHA, suggesting that a more rapid apatite formation on BG was related to solution-mediated dissolution. Primary human osteoblast (HOB) cell model was used to evaluate biological responses to BG nanoparticles. Lactate dehydrogenase (LDH) cytotoxicity assay showed that HOB cells were not adversely affected by the BG nanoparticles throughout the 7day test period. Interestingly, MTS assay results showed an enhancement in cell proliferation in the presence of BG when compared to HA and SiHA nanoparticles. Particularly, statistically significant (p<0.05) alkaline phosphatase (ALP) activity of HOB cells was found on the culture containing BG nanoparticles, suggesting that the cell differentiation might be promoted by BG. Real-time quantitative PCR analysis (qPCR) further confirmed this finding, as a significantly higher level of RUNX2 gene expression was recorded on the cells cultured in the presence of BG nanoparticles when compared to those with HA and SiHA.
采用多步溶胶-凝胶法合成了生物活性玻璃(BG)纳米粒子。透射电子显微镜(TEM)显示,BG 纳米粒子为球形,直径为 30 至 60nm。将 BG 纳米粒子的体外反应性与相似尺寸的羟基磷灰石(HA)和硅取代的羟基磷灰石(SiHA)纳米粒子在磷酸盐缓冲盐水(PBS)、Tris 缓冲液(TRIS)、模拟体液(SBF)和 Dulbecco 修改的 Eagle 培养基(DMEM)中进行了测试。通过傅里叶变换红外光谱(FTIR)分析证实了 BG 纳米粒子的生物活性。结果发现,在 SBF 中浸泡 7 天后形成了类骨磷灰石。含有 BG 纳米粒子的溶液比 HA 和 SiHA 略呈碱性,表明 BG 上更快的磷灰石形成与溶液介导的溶解有关。采用原代人成骨细胞(HOB)细胞模型来评估对 BG 纳米粒子的生物学反应。乳酸脱氢酶(LDH)细胞毒性测定表明,在整个 7 天测试期间,HOB 细胞不受 BG 纳米粒子的不良影响。有趣的是,与 HA 和 SiHA 纳米粒子相比,MTS 测定结果显示在存在 BG 的情况下细胞增殖增强。特别是,在含有 BG 纳米粒子的培养物中发现 HOB 细胞的碱性磷酸酶(ALP)活性具有统计学意义(p<0.05),表明 BG 可能促进细胞分化。实时定量 PCR 分析(qPCR)进一步证实了这一发现,因为与含有 HA 和 SiHA 的细胞相比,在含有 BG 纳米粒子的细胞中记录到 RUNX2 基因表达水平显著更高。