磷酸化壳聚糖膜的仿生复合修饰

仿生构建羟基磷灰石/壳聚糖复合材料是制备骨修复材料的一条有效途径.以甲醛和磷酸为反应试剂,采用均相反应法制备出壳聚糖(CS)的磷酸化衍生物-甲基磷酸化壳聚糖(NPCS).红外光谱、X射线光电子能谱分析结果表明,改性后的CS分子结构和元素组成发生显著变化,偶合等离子体发射光谱测试显示NPCS的取代度可达到0.5左右.用模拟体液(SBF)处理CS和NPCS膜,扫描电镜(SEM)观察和能量色散X射线分析表明,NPCS膜表面沉积了磷酸钙盐.由X射线衍射分析得知,NPCS膜表面形成的是低结晶度的羟基磷灰石(HA).接触角测试结果表明,经改性或修饰后,材料表面的亲水性明显提高.

Biomimetic Modification of Phosphonized Chitosan Membrane

Biomimetic growth of calcium phosphate over chitosan might be an effective approach to constitute inorganic/organic composite biomaterial. In this study, N-methylene phosphonic chitosan (NPCS) was synthesized via formaldehyde addition and condensation with phosphoric acid in a step reaction. The NPCS obtained was characterized by FTIR, XPS and ICP analyses. A stimulated body fluid was used to deposit hydroxyapatite(HA) on the surfaces of NPCS film. SEM and water contact angle measurement were performed to evaluate the surface texture and hydrophilicity of the materials. The data of XRD and EDX demonstrated that HA layer deposited on NPCS film surface in a SBF, has a low crystallinity with n(Ca)/n(P) being nearly 1.60 when immersing time extended for 20 days.