Yao Qingqing, Yang Yun, Pu Ximing, Yang Liulin, Hou Zhenqing, Dong Yanming, Zhang Qiqing
a Department of Chemistry , College of Chemistry and Chemical Engineering, and The Key Laboratory of Analytical Sciences of the Ministry of Education, Xiamen University , Xiamen , 361005 , P. R. China.
J Biomater Sci Polym Ed. 2012;23(14):1755-70. doi: 10.1163/092050611X597780. Epub 2012 May 8.
Calcium-deficient hydroxyapatite (cd-HA) crystals with a rod-like shape, 10-30 nm in diameter and 60150 nm in length, were prepared via a hydrothermal method in the presence of poly(acrylic acid) (PAA) (in situ HA). Scaffolds composed of chitosan (CS), polycaprolactone (PCL) and in situ HA were prepared by freeze-drying, using a formic acid/acetone mixture as a shared solvent. The mass fraction of in situ HA in the scaffolds ranged from 0 to 40%. FT-IR and XRD studies indicated that hydrogen bonding interactions existed among CS, PCL and in situ HA, which suppressed the crystallization of PCL. The mechanical results demonstrated that the CS/PCL composites had the maximum flexural stress (308.14 ± 8.86 MPa), which was significantly higher than 2.92 ± 0.02 MPa for the CS/in situ HA control. The effects of scaffolds on MC3T3-E1 cells were studied by measuring the viability, proliferation, adhesion, alkaline phosphatase activity, as well as mineralization assay. The WST-1 assay showed that in situ HA-loaded scaffolds had higher cell viability than CS/PCL scaffolds. SEM images of the cell-seeded scaffolds revealed a significant promotion of cell adhesion in in situ HA-loaded scaffolds. Moreover, ALP and mineralization were found to be enhanced in in situ HA-loaded scaffolds. All these results indicate that in situ HA-loaded scaffolds support cellular functions of osteoblastic cells and may serve as promising bone scaffolds.
通过水热法在聚丙烯酸（PAA）存在下制备了直径为10 - 30nm、长度为60 - 150nm的棒状缺钙羟基磷灰石（cd - HA）晶体（原位HA）。以甲酸/丙酮混合液作为共溶剂，通过冷冻干燥制备了由壳聚糖（CS）、聚己内酯（PCL）和原位HA组成的支架。支架中原位HA的质量分数范围为0至40%。傅里叶变换红外光谱（FT - IR）和X射线衍射（XRD）研究表明，CS、PCL和原位HA之间存在氢键相互作用，这抑制了PCL的结晶。力学结果表明，CS/PCL复合材料具有最大弯曲应力（308.14±8.86MPa），显著高于CS/原位HA对照组的2.92±0.02MPa。通过测量细胞活力、增殖、黏附、碱性磷酸酶活性以及矿化分析，研究了支架对MC3T3 - E1细胞的影响。WST - 1分析表明，负载原位HA的支架比CS/PCL支架具有更高的细胞活力。接种细胞的支架的扫描电子显微镜（SEM）图像显示，负载原位HA的支架中细胞黏附得到显著促进。此外，发现负载原位HA的支架中碱性磷酸酶和矿化作用增强。所有这些结果表明，负载原位HA的支架支持成骨细胞的细胞功能，可能是有前景的骨支架。
