骨组织工程用纳米羟基磷灰石/细菌纤维素的体外降解行为研究(英文)

In vitro Degradation Performance of Nano-Hydroxyapatite/Bacterial Cellulose for Bone Tissue Engineering

将细菌纤维素浸泡在模拟体液中沉积而形成的纳米羟基磷灰石/细菌纤维素复合材料(nano-HA/BC),被认为是在骨组织工程领域中理想的支架材料。从以下几方面分析nano-HA/BC在磷酸盐缓冲液(PBS)中浸泡不同时间后的降解行为及其相应的机制:材料的降解程度、nano-HA颗粒的稳定性和BC的结构变化。结果表明,nano-HA/BC在PBS溶液中浸泡一定时间后,nano-HA颗粒会逐渐溶解或脱落,水分子直接与BC纤维丝相互作用。在水分子和离子的作用下,BC的结晶度降低,BC分子链中分子间和分子内的结合力降低,甚至部分非结晶区内C—O—C键断裂。而C—O—C键的断裂是nHA/BC在PBS溶液中BC大分子降解的主要机制。研究结果对于研究骨组织工程支架材料nHA/BC的体内降解行为具有重要的指导意义。

Nano-hydroxyapatite/bacterial cellulose （nano-HA/BC） composite, obtained by depositing in simulated body fluid, is expected to have potential applications in tissue engineering. The in-vitro degradation performance and the corresponding mechanism of nano-HA/BC immersed in phosphate buffer solution （PBS） are investigated with several flakes of nano-HA/BC soaked in PBS for different time. The degradation degree of materials, the stability of nano-HA particles and the swelling and structural changes of BC are analysed successively. The results indicate that nano-HA particles are able to dissolve or drop off gradually and that water molecules attack the BC fibrils. So the bonding strength of molecular chains is weakened and the partial C--O--C bonds disconnect. The disconnection of C--O--C bonds is considered as the primary reason for the degradation of BC large molecular chains after nHA/BC is immersed in PBS. The present work is available for controlling the in vivo degradation performance of nHA/BC acting as bone tissue engineered scaffold materials.