Department of Novel Drug Delivery Systems, Iran Polymer and Petrochemical Institute, PO Box 14965/115, Tehran, Iran.
J Biomed Mater Res A. 2011 Aug;98(2):257-67. doi: 10.1002/jbm.a.33108. Epub 2011 May 27.
In this work, two unsaturated derivatives of polycaprolactone (PCL), polycaprolactone fumarate (PCLF), and polycaprolactone itaconate (PCLI), have been synthesized and used as an infiltrating polymer to improve the mechanical properties of brittle hydroxyapatite (HA) scaffolds. PCLF and PCLI were first synthesized through polyesterification of the low molecular weight PCL diols with fumaryl chloride and itaconyl chloride respectively, and then characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography, and differential scanning calorimetry analysis. HA scaffolds were sintered using a foam replication technique, with porosity of about 60%. Polymer-HA composites were obtained by infiltrating the HA scaffolds with PCLF and PCLI solution (12.5 and 30 w/v in dichloromethane) followed by thermal crosslinking. The polymer infiltrated HA scaffolds were characterized by scanning electron microscopy, porosimetry, and gravimetrical analysis. The polyesterification reaction of PCL diols with fumarate chloride was more efficient than itaconyl chloride and dependent upon the molecular weight of the initial PCL precursor; the resultant PCLF demonstrated a degree of substitution of 1.2, 4.2, and 2.7 times higher than PCLIs. Polymer infiltration improved the compressive strength of the HA scaffolds, and based upon the type of macromer (PCLF or PCLI) and also their concentration in infiltrating solution (12.5 or 30 w/v %) compressive strength increased about 14-328%. In all studied samples, the reinforcement effect of PCLF infiltration was higher than PCLI. The macromers and their corresponding infiltrated HA scaffolds did not show any significant cytotoxicity toward human primary osteogenic sarcoma cell (G92 cell lines), in vitro.
在这项工作中，合成了两种不饱和聚己内酯（PCL）衍生物，富马酸聚己内酯（PCLF）和衣康酸聚己内酯（PCLI），并将其用作渗透聚合物以改善脆性羟基磷灰石（HA）支架的机械性能。首先通过低分子量 PCL 二醇与富马酰氯和衣康酰氯的聚酯化反应分别合成了 PCLF 和 PCLI，然后通过傅里叶变换红外光谱、核磁共振波谱、凝胶渗透色谱和差示扫描量热分析进行了表征。使用泡沫复制技术烧结 HA 支架，其孔隙率约为 60%。通过将 PCLF 和 PCLI 溶液（二氯甲烷中的 12.5 和 30 w/v）渗透到 HA 支架中，然后进行热交联来获得聚合物-HA 复合材料。通过扫描电子显微镜、孔隙率和重量分析对聚合物渗透的 HA 支架进行了表征。PCL 二醇与富马酸氯的聚酯化反应比衣康酸氯更有效，并且取决于初始 PCL 前体的分子量；所得的 PCLF 的取代度分别比 PCLI 高 1.2、4.2 和 2.7 倍。聚合物渗透提高了 HA 支架的抗压强度，并且基于大分子单体（PCLF 或 PCLI）的类型及其在渗透溶液中的浓度（12.5 或 30 w/v%），抗压强度提高了约 14-328%。在所有研究的样品中，PCLF 渗透的增强效果均高于 PCLI。大分子单体及其相应的渗透 HA 支架在体外对人原代成骨肉瘤细胞（G92 细胞系）没有显示出任何明显的细胞毒性。
