Biomaterials and Tissue Engineering Laboratory, Department of Nanobiomedical Science & WCU Research Center, Dankook University Graduate School, Cheonan, South Korea.
J Mater Sci Mater Med. 2011 May;22(5):1257-68. doi: 10.1007/s10856-011-4296-5. Epub 2011 Apr 2.
Here, we prepared self-setting calcium phosphate cements (CPCs) based on α-tricalcium phosphate with the incorporation of sodium alginate, and their mechanical properties and in vitro cellular responses were investigated. The addition of alginate enhanced the hardening reaction of CPCs showing shorter setting times within a range of powder-to-liquid ratios. When immersed in a body simulating fluid the alginate-CPCs fully induced a formation of an apatite crystalline phase similar to that of bare CPCs. The compressive and tensile strengths of the CPCs were found to greatly improve during immersion in the fluid, and this improvement was more pronounced in the alginate-CPCs. As a result, the alginate-CPCs retained significantly higher strength values than the bare CPCs after 3-7 days of immersion. The rat bone marrow derived stromal cells (rBMSCs) cultured on the alginate-CPCs initially adhered to and then spread well on the cements surface, showed an on-going increase in the population with culture time, and differentiated into osteoblasts expressing bone-associated genes (collagen type I, osteopontin and bone sialoprotein) and synthesizing alkaline phosphatase. However, the stimulated level of osteogenic differentiation was not confirmative with the incorporation of alginate into the CPC composition based on the results. One merit of the use of alginate was its usefulness in forming CPCs into a variety of scaffold shapes including microspheres and fibers, which is associated with the cross-link of alginate under the calcium-containing solution.
在这里，我们基于α-磷酸三钙制备了自固化磷酸钙骨水泥（CPCs），并研究了它们的机械性能和体外细胞反应。海藻酸钠的加入增强了 CPCs 的硬化反应，在一定的粉末-液体比例范围内缩短了凝固时间。当浸泡在模拟体液中时，海藻酸盐-CPC 完全诱导形成与裸 CPC 相似的磷灰石结晶相。研究发现，CPC 在浸泡在液体中的抗压和抗拉强度有了很大的提高，而在海藻酸盐-CPC 中提高更为明显。因此，海藻酸盐-CPC 在浸泡 3-7 天后保持比裸 CPC 更高的强度值。在海藻酸盐-CPC 上培养的大鼠骨髓基质细胞（rBMSCs）最初附着在水泥表面上并很好地扩散，随着培养时间的延长，细胞数量持续增加，并分化为表达骨相关基因（I 型胶原、骨桥蛋白和骨涎蛋白）和合成碱性磷酸酶的成骨细胞。然而，基于结果，骨向分化的刺激水平与海藻酸盐在 CPC 组成中的加入并不一致。海藻酸盐的一个优点是其在将 CPC 形成各种支架形状（包括微球和纤维）方面的有用性，这与海藻酸盐在含钙溶液中的交联有关。
