Zheng Kai, Bortuzzo Judith A, Liu Yufang, Li Wei, Pischetsrieder Monika, Roether Judith, Lu Miao, Boccaccini Aldo R
Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany.
Food Chemistry Unit, Department of Chemistry and Pharmacy, Emil Fischer Center, University of Erlangen-Nuremberg, Schuhstr. 19, 91052 Erlangen, Germany.
Colloids Surf B Biointerfaces. 2015 Nov 1;135:825-832. doi: 10.1016/j.colsurfb.2015.03.038. Epub 2015 Mar 23.
Hierarchically porous bioactive glass particles (BGPs) were synthesized by a facile sol-gel process using pollen grains as the templates. The synthesized pollen-templated bioactive glass particles (PBGPs) exhibited dual macro-nano porous structure. The macro pores (∼ 1 μm) were inherited from the template of pollen grains while the nano pores (∼ 9.5 nm) were induced by the intrinsic mechanism of the sol-gel process. PBGPs possessed a high specific surface area (111.4m(2)/g) and pore volume (0.35 cm(3)/g). Hydroxyapatite (HA) formation on PBGPs was detected within 3 days after immersion in simulated body fluid (SBF). Due to their larger specific surface area and pore volume, PBGPs could be loaded with more tetracycline hydrochloride (TCH) than non-templated BGPs and conventional melt-derived 45S5 BGPs. In addition, PBGPs exhibited a low initial burst release (within 10% of the loaded amount) within 18 h and a sustained release with a two-stage release pattern for up to 6 days in phosphate buffered saline (PBS). The antibacterial assay confirmed that the TCH-loaded PBGPs could release TCH within 5 days, and the released TCH could reach the minimum inhibitory concentration (MIC) against Escherichia coli. MTT assay indicated that PBGPs showed non-cytotoxic effects toward human hepatocellular carcinoma (Hep G2) cells after co-culture for up to 72 h in vitro. These results showed that the biocompatible hierarchically macro-nano porous PBGPs are potential for bone regeneration and local drug delivery applications.
采用简便的溶胶-凝胶法，以花粉颗粒为模板合成了具有分级多孔结构的生物活性玻璃颗粒（BGPs）。合成的花粉模板生物活性玻璃颗粒（PBGPs）呈现出双宏观-纳米多孔结构。宏观孔（约1μm）继承自花粉颗粒模板，而纳米孔（约9.5nm）则由溶胶-凝胶过程的内在机制诱导形成。PBGPs具有较高的比表面积（111.4m²/g）和孔体积（0.35cm³/g）。将PBGPs浸泡在模拟体液（SBF）中3天内即可检测到羟基磷灰石（HA）的形成。由于其较大的比表面积和孔体积，PBGPs比非模板化BGPs和传统熔融法制备的45S5 BGPs能负载更多的盐酸四环素（TCH）。此外，PBGPs在18小时内表现出较低的初始突释（低于负载量的10%），并在磷酸盐缓冲盐水（PBS）中以两阶段释放模式持续释放长达6天。抗菌试验证实，负载TCH的PBGPs可在5天内释放TCH，释放的TCH可达到对大肠杆菌的最低抑菌浓度（MIC）。MTT试验表明，PBGPs与人类肝癌（Hep G2）细胞共培养长达72小时后对细胞无细胞毒性作用。这些结果表明，具有生物相容性的分级宏观-纳米多孔PBGPs在骨再生和局部药物递送应用方面具有潜力。
