Rodríguez-Lorenzo L M, Salinas A J, Vallet-Regí M, San Román J
Departmento de Química Inorgánica y Bioinorgánica, Facultad de Farmacia, U.C.M., Madrid, Spain.
J Biomed Mater Res. 1996 Apr;30(4):515-22. doi: 10.1002/(SICI)1097-4636(199604)30:4<515::AID-JBM10>3.0.CO;2-G.
Composite biomaterials with good mechanical response and a partially biodegradable character were prepared by the free radical polymerization of mixtures of alpha-Al2O3, low-molecular-weight but crystalline poly(L-lactic acid) (PLLA), and methyl methacrylate (MMA). Cylindrical specimens prepared with different composition were characterized by thermogravimetry, calorimetry, 1H-NMR spectroscopy, and x-ray diffraction (XRD). The in vitro biodegradative process was studied in different media, following variations of the pH, gravimetric weight loss of the specimens, and crystalline domain change by XRD after immersion in pure water and buffered solutions at pH 4.0 and pH 8.0 for 90 days. Formation of a relatively porous structure with good cohesion after the biodegradative treatment (confirmed by SEM) was observed. These systems can be considered for applications in orthopedic surgery as filling biomaterials and even as control drug-delivery systems.
通过α-Al2O3、低分子量但结晶的聚（L-乳酸）（PLLA）和甲基丙烯酸甲酯（MMA）混合物的自由基聚合制备了具有良好力学响应和部分可生物降解特性的复合生物材料。用不同组成制备的圆柱形试样通过热重分析、量热法、1H-NMR光谱和X射线衍射（XRD）进行表征。在不同介质中研究了体外生物降解过程，跟踪pH值变化、试样的重量损失以及在pH 4.0和pH 8.0的纯水和缓冲溶液中浸泡90天后通过XRD观察到的结晶域变化。观察到生物降解处理后形成了具有良好内聚力的相对多孔结构（通过扫描电子显微镜确认）。这些体系可考虑用于整形外科手术，作为填充生物材料，甚至作为控释药物递送系统。
