Divisão de Biomateriais, INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
J Biomed Mater Res A. 2010 Dec 1;95(3):891-900. doi: 10.1002/jbm.a.32916.
To modulate the biological response of implantable granules, two types of bioactive porous granules composed of nanostructured-hydroxyapatite (HA) agglomerates and microstructured-HA, respectively, were prepared using a polyurethane sponge impregnation and burnout method. The resulting granules presented a highly porous structure with interconnected porosity. Both types of granules were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and mercury intrusion porosimetry. Results showed that nanostructed-HA granules presented higher surface area and porosity than microstructured-HA granules. In vitro testing using MG63 human osteoblast-like cells showed that on both types of surfaces cells were able to adhere, proliferate, and migrate through the macropores, and a higher growth rate was achieved on nanostructured-HA granules than on microstructured-HA granules (76 and 40%, respectively). In addition, these cells maintained similar expression levels of osteoblastic-associated markers namely collagen type I, alkaline phosphatase, bone morphogenetic protein-2, macrophage colony-stimulating factor, and osteoprotegerin. These innovative nanostructured-HA granules may be considered as promising bioceramic alternative matrixes for bone regeneration and drug release application.
为了调节可植入颗粒的生物响应，使用聚氨酯海绵浸渍和烧蚀法制备了两种由纳米结构-羟基磷灰石（HA）团聚体和微结构-HA 组成的生物活性多孔颗粒。得到的颗粒呈现出高度多孔的结构，具有连通的孔隙。使用傅里叶变换红外光谱（FTIR）、X 射线衍射（XRD）、扫描电子显微镜（SEM）和压汞法对两种类型的颗粒进行了表征。结果表明，纳米结构-HA 颗粒的比表面积和孔隙率高于微结构-HA 颗粒。体外使用 MG63 人成骨样细胞进行测试表明，在两种类型的表面上，细胞都能够附着、增殖并通过大孔迁移，并且在纳米结构-HA 颗粒上的生长速度高于在微结构-HA 颗粒上的生长速度（分别为 76%和 40%）。此外，这些细胞保持了相似的成骨相关标志物的表达水平，即胶原蛋白 I、碱性磷酸酶、骨形态发生蛋白-2、巨噬细胞集落刺激因子和骨保护素。这些创新的纳米结构-HA 颗粒可被视为用于骨再生和药物释放应用的有前途的生物陶瓷替代基质。
