透明质酸/壳聚糖复合支架的制备及其力学性能评价

目的　模拟天然骨组织的结构和成分，寻找适合骨组织工程的新型支架材料。 方法 以透明质酸、壳聚糖为基质材料，在微酸性环境中以一定配比与氯化钙和磷酸二氢钠混合，冷冻干燥得到多孔复合支架材料。然后在乙醇/水/尿素环境中分别陈化0、2、4、8、12和24 h，以生成产物钙磷盐前驱体转变为羟基磷灰石，最终制备出一种深度矿化的透明质酸/壳聚糖复合支架。并通过SEM、EDS等对支架进行表征，研究支架的形貌、成分及力学强度等性能。 结果 SEM观察显示，支架材料具有比较均匀的多孔结构，孔径大小为100~200 μm。EDS结果表明，复合支架在一次冻干之后形成的是磷酸氢钙（DCPD）,随着陈化时间的延长，DCPD逐渐向羟基磷灰石（HAP）转化。而压缩强度则表明经过原位矿化的支架力学性能显著提高。 结论 通过该法得到的透明质酸/壳聚糖复合支架可作为骨组织工程的新型支架材料。

Preparation and in-situ mineralization of sodium hyaluronate and chitosan

Objective 　To imitate the structure and composition of natural bone，a ternary composite scaffold was constructed in this paper.    Methods    Sodium hyaluronate (HA) solution with calcium chloride were added dropwise to chitosan (CS) solution with sodium dihydrogenphosphate solution under high speed stirring. Then the mixture was freeze-dried and then aged in ethanol/water/ urea solution to prepare the HA/CS/HAP porous composite scaffold in situ. The morphology, composition and mechanical property were studied in this research.    Results    SEM results showed the scaffold  was porous, sponge-like  with uniform pores with diameter of 100-200 µm. EDS results indicated DCPD was first formed after freeze-drying and the extension of aging time contributed to the transition from DCPD to HA.　Conclusion　The HA/CS/HAP porous composite scaffold can be used as a basic scaffold material in tissue engineering.