Department of Polymer Materials, Vanung University, Chung-Li, Taiwan.
Molecules. 2012 Dec 20;18(1):27-40. doi: 10.3390/molecules18010027.
Bioactive composites that enable the formation of calcium phosphates have received increased attention over the last decade, in the development of osteoconductive biomaterials for orthopaedic applications. In this work, tripolyphosphate (TPP)-cross-linked chitosan/gelatin composites (TPP-CG) were prepared for the growth of shape- and size-controlled calcium phosphates on/in the composites. The mineralization pattern of the composites, after soaking in the Ca(OH)(2) aqueous solution, clearly demonstrated oriented, needle-like nanocrystallites of calcium phosphates in the matrix with especially high Ca/P molar ratio (3.98) as detected by energy dispersive X-ray spectroscopy (EDX) analysis. Subsequent to mineralization in a simulated body fluid (SBF), the mineralized composites showed micro-scaled spherical aggregates deposited on the surface and granule-like nanocrystallites grew in the matrix. The Ca/P molar ratio (1.72) and X-ray diffraction pattern of the nanocrystallites grown in the composites were similar to those of hydroxyapatite (HAp). Osteoblastic differentiation of ROS cells cultured on the mineralized composites allowed an enhanced expression of the chosen osteogenic marker (alkaline phosphatase, ALPase). These results indicated that the composites mineralized with micro- and nano-scaled calcium phosphates with various structural features make them attractive for bone tissue engineering applications.
在过去十年中，在开发用于骨科应用的骨传导生物材料方面，能够形成磷酸钙的生物活性复合材料受到了越来越多的关注。在这项工作中，制备了三聚磷酸酯（TPP）交联壳聚糖/明胶复合材料（TPP-CG），以在复合材料上/内生长形状和尺寸可控的磷酸钙。将复合材料浸泡在 Ca(OH)(2)水溶液中后，复合材料的矿化模式通过能量色散 X 射线光谱（EDX）分析清楚地表明了具有特别高的 Ca/P 摩尔比（3.98）的基质中的定向、针状纳米晶磷酸钙。在模拟体液（SBF）中矿化后，矿化复合材料显示出沉积在表面上的微尺度球形聚集体和在基质中生长的颗粒状纳米晶。在复合材料中生长的纳米晶的 Ca/P 摩尔比（1.72）和 X 射线衍射图案与羟基磷灰石（HAp）相似。在矿化复合材料上培养的成纤维细胞 ROS 的成骨细胞分化允许选择的成骨标志物（碱性磷酸酶，ALPase）的表达增强。这些结果表明，用具有各种结构特征的微纳米级磷酸钙矿化的复合材料使其成为骨组织工程应用的有吸引力的材料。
