背景:聚富马酸丙二醇酯具有室温固化特性,β-磷酸三钙具有良好的生物相容性,但是目前缺乏聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥的系统研究。目的:制备聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥,考察其体外生物活性和降解性。方法:采用液相沉淀法制备β-磷酸三钙,两步法合成聚富马酸丙二醇酯高分子,制备可注射聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥。(1)体外矿化:将聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥、聚甲基丙烯酸甲酯骨水泥分别浸泡于模拟体液中7 d,检测材料表面羟基磷灰石沉积。(2)体外降解:将聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥浸泡于PBS中,在相应的时间点检测吸水率、失重率、体系pH值、压缩强度及表面和断面形貌变化。结果与结论:(1)体外矿化:可注射聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥表面能够沉积羟基磷灰石,聚甲基丙烯酸甲酯骨水泥表面未沉积羟基磷灰石;(2)体外降解:聚富马酸丙二醇酯/β-磷酸三钙在PBS中63 d内体系pH值稳定,材料降解温和;84 d材料失重率为13.5%;扫描电镜显示聚富马酸丙二醇酯/β-磷酸三钙表面为溶蚀降解,压缩强度随着降解时间延长逐渐降低,有利于降解过程中力学性能的完整性和持续性;(3)结果表明:聚富马酸丙二醇酯/β-磷酸三钙复合骨水泥是一种具备体外矿化和降解能力的材料。
BACKGROUND:Poly(propylene fumarate) (PPF) can crosslink at room temperature, andβ-tricalcium phosphate (β-TCP) has good biocompatibility, but PPF/β-TCP composite bone cement has not yet been systematical y studied. OBJECTIVE:To prepare PPF/β-TCP composite bone cement and to explore its in vitro bioactivity and degradability. METHODS:β-TCP and PPF were respectively synthesized by liquid-phase precipitation and a two-step method, and PPF/β-TCP composite bone cement was prepared through mixing PPF withβ-TCP. The in vitro bioactivity of PPF/β-TCP was compared with the commercial poly(methyl methacrylate) (PMMA) through the ability of forming hydroxyapatite after immersed in simulated body fluid for 7 days. The in vitro degradability of PPF/β-TCP was studied via investigating the transformation of pH values, water uptake and mass loss, compressive strength and morphology at each time point. RESULTS AND CONCLUSION:There were hydroxyapatites formed on the PPF/β-TCP material, but none on the commercial PMMA material. The pH values of the PPF/β-TCP were stable in PBS for 63 days, indicating its degradation is moderate;the mass loss was up to 13.5%after 84 days. Scanning electron microscope displayed the degraded PPF/β-TCP surface, and its compressive strength was decreased gradual y, which good for the integrity and sustainability of mechanical properties during degradation. These results suggest that PPF/β-TCP bone cement holds mineralization and degradability in vitro.