【摘要】 采用电化学辅助技术控制阴、阳两极溶液中的钙、磷离子定向迁移,进入壳聚糖多孔支架内部发生反应并在孔隙表面沉积,制备了有机-无机复合多孔支架.应用XRD、SEM、煅烧法、孔隙率测定和压缩实验对支架的组成、形貌、无机物沉积量、孔隙率以及压缩强度进行了表征.研究表明,处理后支架孔隙表面沉积了低结晶度的羟基磷灰石,低倍下沉积层均匀致密,在高的放大倍数下发现,沉积层中存在大量的微孔,沉积层表面存在着球状物,该球状物是由许多小片组成的.沉积6 h时沉积量为支架质量的2.81%,支架孔隙率由96.0%减少到89.8%.与纯壳聚糖支架相比,复合支架的压缩强度由0.0550 MPa提高到0.0998 MPa.更多还原

【Abstract】 Natural biopolymer chitosan has been investigated widely for a variety of biomedical applications due to its excellent biocompatibility and biodegradability.The toughness of chitosan porous scaffolds is good,but the strength is low.It is suggested that the coating treatment of hydroxyapatite will improve the strength and osteo-conductivity of the scaffolds,and maintain the toughness still.In this research,the electrochemistry assisted deposition method was used to deposit hydroxyapatite on the pores’ surface of porous scaffolds.Calcium and phosphate ions in anode and cathode solutions moved directionally in the electric field,reached the internal of scaffolds and reacted and deposited,so the organic-inorganic composite scaffold was obtained.The composition,morphology,inorganic deposition amount,porosity and compressive strength were characterized by XRD,SEM,calcination,porosity measurement,and compression experiment.It was shown that the hydroxyapatite coating with low crystallinity deposited on the pores’ surface of scaffolds.The coating was uniform and dense at low magnification,but there was a great deal of micropores in the deposition layer at high magnification,and some spheres on the layer composed of small hydroxyapatite lamellae.After being treated 6 h,the deposition amount was 2.81% of total weight,and the porosity was decreased from 96.0% to 89.8%.The compressive strength of the treated scaffold was increased to 0.0998 MPa comparing with 0.0550 MPa of the chitosan scaffold.更多还原