一种可注射自固化含锶复合胶原磷酸钙骨水泥的结构和性能

Structure and performance of injectable strontium-contained collagen calcium phosphate cement

背景:骨科学界正致力于磷酸钙骨水泥的改性研究,通过向磷酸钙骨水泥中加入不同的添加剂,包括固化促进剂、增塑剂、抗水/血溶剂、致孔剂、增强剂,或是将生物活性物质或药物复合到磷酸钙骨水泥中,以提高其理化和生物学性能是目前该领域的研究热点。目的:了解一种新型可注射可降解的磷酸钙骨水泥的理化性能。设计、时间及地点:重复测量试验,于2008-12/2009-05在华南理工大学材料学院国家重点实验室完成。材料:采用部分结晶的磷酸钙,部分结晶的磷酸锶和二水磷酸氢钙,添加改性淀粉﹑Ⅰ型胶原制备了新型可注射自固化磷酸钙骨水泥。方法:采用X’PertPro型X射线衍射仪对磷酸钙骨水泥固化体进行相分析。采用HITA2-CHIH-800型透射/扫描电子显微镜对磷酸钙骨水泥固化体的形貌进行观察。用维卡仪根据美国材料与试验协会ASTMC190203标准进行凝结时间的测试。使用Instron5567型万能电子材料试验机来测试固化样品的抗压强度。用注射器测试材料的可注射性,针头内径为1.6mm。通过浸泡摇动定性测试材料的抗溃散性。主要观察指标:①骨水泥水化产物的相组成和显微结构。②骨水泥的凝固时间、可注射性和抗压强度。③骨水泥的抗溃散性。结果:研究表明该材料具备优良的可注射性能;添加改性淀粉显著的改善了骨水泥的抗溃散性。随着骨水泥液固比的增大,骨水泥的抗压强度下降,当骨水泥的液固比为0.3时,骨水泥的抗压强度为(48.0±2.3)MPa,当骨水泥的液固比为0.6时,骨水泥的抗压强度下降为(21.0±2.5)MPa。骨水泥的水化产物为类骨羟基磷灰石结晶,从X射线衍射图谱还可以看出,因骨水泥的水化不完全,基线水平波动较大,说明了在充分水化的条件下,骨水泥的压缩强度还能进一步提高。结论:制备的可注射含锶复合胶原磷酸钙骨水泥符合人体生物力学强度,能满足手术条件要求。

BACKGPOUND： Orthopedic academics are committed to the modification of calcium phosphate cement （CPC） by adding different additives, including the promotion of curing agents, piasticizers, anti-water blood solvent, porogen, enhancer, or biological activity substance or drug compound to the CPC in order to enhance its physical and chemical and biological properties which is a research hotspot in the field.OBJECTIVE： To investigate the physical and chemical characteristics of a biodegradable injectable CPC. DESIGN,TIME AND SETTING： Duplicated testing study was performed at the National Key Laboratory, College of Materials, South China University of Technology from December 2008 to May 2009. MATERIALS： Calcium phosphate with partial crystallization and strontium phosphate and calcium hydrogen phosphate dehydrate with partial crystallization were added with modified starch and type I collagen to prepare a new type of seJf-injectable CPC. METHODS：CPC phase was analyzed using X＇Pert Pro X-ray diffractometer; CPC morphology was observed using HITA2 -CHIH-800 transmission/scanning electron microscope; setting-up time was tested using Vicat apparatus according to A S TM C190203 standard; compressive strength was measured using Instron 5567 omnipotent electron apparatus; syringeability was detected using sydnge apparatus with 1.6 mm of inside diameter; collapsibility was tested using soaking-shaking quantitative materials.MAIN OUTCOME MEASURES： Phase component and microstructure of CPC products, setting-up time, syringeability, compressive strength, and collapsibility. RESULTS： The material coul be injected with an excellent performance, and the modified starch significantly improved the resistance of bone cement collapsibility. As the bone cement liquid-solid ratio increased, the compressive strength of cement decreased. When the bone cement liquid-solid ratio was 0.3, the compressive strength for cement was （48.0±2.3） MPa; when the bone cement liquid-solid ratio was 0.6, the compressive strength of bone cement reduced to （21.0±2.5） MPa. Hydration product of cement-like bone hydroxyapatite crystallization also could be seen from the X-ray diffraction, due to the hydration of cement was not complete, a baseline level of volatile explained fully hydrated conditions, suggesting that the bone cement could further improve the compression strength. CONCLUSION： Developed an injectable strontium-contained collagen CPC is coincidence with the biomechanical strength of the human body and meets the requirements of the operation conditions.