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以多聚磷酸钠(TPP)为交联剂,采用乳化交联法制备了牛血清白蛋白(BSA)壳聚糖控释微球(CMs)。将微球与纳米羟基磷灰石/胶原(nHAC)、聚乳酸(PLA)按不同比例混合,采用热致分相法制备了CMs/nHAC/PLA复合支架材料。利用扫描电镜、激光粒度分析仪、压汞仪和力学性能测试仪考察了微球与复合支架的性能。结果表明:所制备的壳聚糖微球形态良好,呈规则球形,粒径主要分布在20~50μm;随BSA初始用量的增加,微球的载药量从0.78%增大到2.74%,但包封率从86.9%下降到78.4%;控制CMs用量不超过PLA质量的30%,则可保证微球在CMs/nHAC/PLA中的均匀分布,此时复合材料的孔径主要分布在100~200μm,孔隙率不低于83.1%,压缩强度在1~2 MPa。这种复合支架材料可望作为人体非承重部位的植入骨修复体和组织工程支架使用。
Bovine Serum Albumin (BSA) chitosan controlled release microspheres (CMs) were prepared by emulsion cross-linking method using sodium polyphosphate (TPP) as the crosslinking agent. The microspheres were mixed with nano-hydroxyapatite / collagen (nHAC) and polylactic acid (PLA) in different proportions. CMs / nHAC / PLA composite scaffold materials were prepared by thermal induced phase separation. The properties of microspheres and composite scaffolds were investigated by scanning electron microscopy, laser particle size analyzer, mercury porosimetry and mechanical properties tester. The results showed that the prepared chitosan microspheres were in good shape and spherical in shape with particle sizes of 20-50 μm. The loading of microspheres increased from 0.78% to 2.74% with the increase of the initial amount of BSA, The entrapment efficiency decreased from 86.9% to 78.4%. When CMs content did not exceed 30% of the mass of PLA, the uniform distribution of microspheres in CMs / nHAC / PLA could be guaranteed. At this time, the pore size of the composites was mainly distributed in the range of 100 ~ 200μm , Porosity of not less than 83.1%, compressive strength of 1 ~ 2 MPa. This composite scaffold is expected to be used as an implantable bone prosthesis and a tissue engineering scaffold for non-load-bearing parts of the body.