Li Jiashen, Beaussart Audrey, Chen Yun, Mak Arthur F T
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Hum, Kowloon, Hong Kong, China.
J Biomed Mater Res A. 2007 Jan;80(1):226-33. doi: 10.1002/jbm.a.31096.
Strategies to bone tissue engineering have focused on the use of synthetic or natural degradable materials as scaffolds for cell transplantation to guide bone regeneration. Biocompatibility, biodegradability, biomechanical integrity, and osteoconductivity are important requirements for the scaffold materials. This study explored a new approach of apatite coating to enhance the osteoconductivity of a synthetic degradable poly(DL-lactic-co-glycolic acid) (PLGA) scaffold. The new approach was developed to ensure a relatively uniform apatite coating on the interior pore surfaces deep inside a scaffold, even for a relatively thick scaffold with small pores. Apatite was first coated on the surface of paraffin spheres of the desirable sizes. The paraffin spheres were then molded to form a foam. PLGA/pyridine solution was cast into the interspaces among the paraffin spheres. After the paraffin spheres were dissolved and removed by cyclohexane, PLGA scaffold with controlled pore size, good interconnectivity and high porosity was obtained with apatite left on the pore surface uniformly throughout the whole scaffold. The scaffold and apatite coating were characterized using thermogravimetry analysis, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffractometry.
骨组织工程策略主要集中于使用合成或天然可降解材料作为细胞移植的支架以引导骨再生。生物相容性、生物降解性、生物力学完整性和骨传导性是支架材料的重要要求。本研究探索了一种新的磷灰石涂层方法，以提高合成可降解聚（DL-乳酸-乙醇酸）（PLGA）支架的骨传导性。开发这种新方法是为了确保在支架内部深处的孔隙表面上形成相对均匀的磷灰石涂层，即使是对于具有小孔的相对较厚的支架也是如此。首先将磷灰石涂覆在所需尺寸的石蜡球表面。然后将石蜡球模制成泡沫。将PLGA/吡啶溶液浇铸到石蜡球之间的间隙中。在用环己烷溶解并去除石蜡球后，获得了具有可控孔径、良好连通性和高孔隙率的PLGA支架，磷灰石均匀地留在整个支架的孔隙表面上。使用热重分析、扫描电子显微镜、能量色散X射线光谱和X射线衍射对支架和磷灰石涂层进行了表征。
