可注射nHA/PU复合多孔骨修复支架制备及表征

兼具良好孔隙率和原位任意塑形固化的可注射复合多孔骨修复材料在临床不规则骨缺损的治疗方面显示出巨大的优势。本研究通过优化双组分设计，以水为发泡剂制备可注射纳米羟基磷灰石/聚氨酯（nHA/PU）复合多孔支架。利用扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）、力学测试及Gillmore针测试等手段对制备的支架进行结构形貌、化学组成、力学性能和固化时间表征。结果表明，本研究制备的可注射nHA/PU复合多孔支架孔隙率高、孔隙贯通性好，孔径分布在100~700μm，适宜细胞和组织向孔内生长；添加20% nHA显著提高了PU支架的力学强度，但降低了支架的孔隙率；可注射支架在8h固化，适宜临床操作。本研究制备的可注射nHA/PU复合多孔支架在不规则骨缺损修复领域具有较大的应用潜力。

Preparation and characterization of injectable nHA/PU composite porous scaffolds for bone repair

Bone defect repair still represents a challenging issue in clinic. Injectable composite materials for bone repair with good porosity and in situ solidification of arbitrary shape have shown great advantages in the treatment of clinical irregular bone defects. In this study, injectable porous nano hydroxyapatite/polyurethane (nHA/PU) composite scaffolds were fabricated with two-component design and using water as foaming agent. Furthermore, the morphology, chemical composition, internal structure, mechanical properties and curing time of the fabricated scaffold were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X ray diffraction (XRD), mechanical testing and Gilmore needle testing. The results showed that the injectable nHA/PU composite porous scaffolds were successfully prepared. The scaffolds had high porosity and good pore connectivity. The pore size distribution was 100—700μm, which was suitable for the growth of cells and tissues into the pores. The addition of 20% nHA significantly improved the mechanical strength of the PU porous scaffolds but reduced the porosity of the scaffolds. The injectable scaffolds solidified in 8h, which was suitable for clinical operation. The injectable nHA/PU composite porous scaffold prepared in this study has great potential in the field of irregular bone defect repair.