纳米羟基磷灰石/壳聚糖-羧甲基纤维素复合支架材料的研究

用冷冻干燥法制备了不同比例的纳米羟基磷灰石/壳聚糖-羧甲基纤维素(n-HA/CS-CMC)无机/有机复合多孔支架材料, 并探讨了其复合机理及无机组分n-HA对复合支架的结构形貌、力学性能、体外降解性能的影响. 结果表明, 其复合支架主要是通过无机组分n-HA均匀分散充填在CS-CMC聚电解质有机网络结构中形成的, 且三组分间有较强的化学键合. 无机组分n-HA的加入使孔结构变得不规则, 孔隙率略有减小, 使复合支架的抗压缩强度提高, 并且可使其体外降解速度减慢. 无机组分n-HA含量为40\%复合支架材料的性能最佳, 有望用作骨组织工程支架材料.

Study on Nano-hydroxyapatite/Chitosan-Carboxymethyl Cellulose Composite Scaffold

Porous composite scaffolds of nano-hydroxyapatite/chitosan/carboxymethyl cellulose (n-HA/CS-CMC) with different weight ratios (0/50/50, 20/40/40, 40/30/30 and 70/15/15, respectively) were prepared by freeze-drying method for bone tissue engineering scaffold. The mechanism of formation of the composite scaffolds and the effects of inorganic component (n-HA) on the porous morphologies, mechanical properties and their degradation rate of n-HA/CS-CMC composite scaffolds were investigated by means of IR, XRD, SEM, TEM, universal material test machine and PBS soaking. The results show that the composite scaffolds is mainly formed through the complexation reaction between the two opposite polyions of CS and CMC, then n-HA is firmly incorporated into the polyelectrolyte matrix of CS-CMC without agglomeration. The addition of inorganic component n-HA into the system of CS-CMC, which decreases slightly the regularity of pores and porosities of the n-HA/CS-CMC composite scaffolds. However, the addition of inorganic component n-HA increases the compressive strength and steps down the in ~vitro degradation of the composite scaffolds. The composite scaffold with weight ratio of inorganic component (n-HA) of 40% is most suitable for bone tissue engineering scaffold in view of its highly interconnected porous structure, high compressive strength and the acceptable degradation rate.