Kawashita M, Nakao M, Minoda M, Kim H-M, Beppu T, Miyamoto T, Kokubo T, Nakamura T
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
Biomaterials. 2003 Jun;24(14):2477-84. doi: 10.1016/s0142-9612(03)00050-4.
Carboxymethylated chitin, gellan gum, and curdlan gels were soaked in a simulated body fluid (SBF) having ion concentrations nearly equal to those of human blood plasma. Some of the gels had been soaked in a saturated Ca(OH)(2) solution, while others had not. The carboxymethylated chitin and gellan gum gels have carboxyl groups, while the curdlan gel has hydroxyl groups. None of the gels formed apatite on their surfaces in the SBF when they had not been subjected to the Ca(OH)(2) treatment, whereas the carboxymethylated chitin and gellan gum gels formed apatite on their surfaces when they had been subjected to the Ca(OH)(2) treatment. The curdlan gel did not form an apatite deposit even after the Ca(OH)(2) treatment. Apatite formation on the carboxymethylated chitin and gellan gum gels was attributed to the catalytic effect of their carboxyl groups for apatite nucleation, and acceleration of apatite nucleation from released Ca(2+) ions. This result provides a guiding principle for obtaining apatite-organic polymer fiber composites. This composite is expected to have an analogous structure to that of natural bone.
将羧甲基化甲壳素、结冷胶和凝胶多糖凝胶浸泡在离子浓度与人体血浆几乎相同的模拟体液（SBF）中。部分凝胶浸泡在饱和氢氧化钙溶液中，而其他凝胶则未浸泡。羧甲基化甲壳素和结冷胶凝胶含有羧基，而凝胶多糖凝胶含有羟基。未经氢氧化钙处理的凝胶在SBF中其表面均未形成磷灰石，而经过氢氧化钙处理的羧甲基化甲壳素和结冷胶凝胶在其表面形成了磷灰石。即使经过氢氧化钙处理，凝胶多糖凝胶也未形成磷灰石沉积物。羧甲基化甲壳素和结冷胶凝胶上磷灰石的形成归因于其羧基对磷灰石成核的催化作用，以及从释放的钙离子加速磷灰石成核。该结果为获得磷灰石 - 有机聚合物纤维复合材料提供了指导原则。预计这种复合材料具有与天然骨类似的结构。
