氨基改性人造颌骨纳米羟基磷灰石/聚乳酸复合材料的制备与表征

Preparation and characterization of the composites of amino-modified artificial jaw nano-hydroxyapatite/polylactic acid

背景:口腔颌骨缺损修复常选择骨移植材料和人工骨替代材料两种,骨移植材料有其优点,但存在免疫反应、来源不足等缺陷,人工骨替代材料作为骨缺损修复材料的应用潜力巨大。目的:探讨侧链接枝氨基改性纳米羟基磷灰石/聚乳酸复合材料作为口腔人造颌骨材料的制备方法,并进行表征。方法:在纳米羟基磷灰石表面赋予氨基,再进行接枝改性,将接枝改性的纳米羟基磷灰石与聚乳酸复合,制作人造颌骨材料,复合材料中接枝改性纳米羟基磷灰石的含量分别为10%,30%,50%,表征材料的理化性能、机械力学性能与细胞相容性。结果与结论:(1)核磁氢谱、傅里叶变换红外光谱、X射线衍射及热失重分析显示,实验成功制备了氨基接枝改性的纳米羟基磷灰石材料;透射电镜下可见,氨基接枝改性的纳米羟基磷灰石材料有机溶剂N,N-二甲基甲酰胺中仍能以纳米尺寸分散,稳定的分散状态可以维持超过180 d;(2)扫描电镜下可见,当复合材料中的改性纳米羟基磷灰石含量为10%,30%时,显示出了优秀的纳米级分散效果;当含量为50%时,改性纳米羟基磷灰石不能均匀分散于聚乳酸体系中;(3)随着改性纳米羟基磷灰石含量的增加,材料的拉伸强度降低、弹性模量升高,综合考虑下复合材料中改性纳米羟基磷灰石含量为10%时具有较好的机械性能;(4)CCK8实验显示,氨基接枝改性的纳米羟基磷灰石(含量为10%)/聚乳酸复合材料对小鼠成纤维细胞无明显的毒性;(5)结果表明,氨基接枝改性纳米羟基磷灰石(含量为10%)/聚乳酸复合材料具有良好的机械力学性能与细胞相容性。

BACKGROUND:Bone graft materials and artificial bone substitutes are often selected for oral maxillofacial defects repair.Bone graft materials have their advantages,but the shortcomings exist such as immune response and insufficient sources.The application potential of artificial bone substitutes as materials for bone defects repair is huge.OBJECTIVE:To explore the method of the preparation and characterization of the composites of amino-grafted nano-hydroxyapatite and polylactic acid as oral artificial jaw materials.METHODS:The graft-modified nano-hydroxyapatite/polylactic acid composites were prepared based on amino-modified hydroxyapatite for making artificial jaws.The content of graft-modified nano-hydroxyapatite in the composite was 10%,30%,and 50%,separately.Physical and chemical properties,mechanical properties,and cytocompatibility of the composite were characterized.RESULTS AND CONCLUSION:(1) The spectroscopy of 1 H nuclear magnetic resonance,Fourier transform infrared spectroscopy,X-ray diffraction,and thermogravimetric analysis showed that the amino modifier diethylene glycol amine phosphate monoester of modified hydroxyapatite was successfully prepared.Under the transmission electron microscope,graft-modified nano-hydroxyapatite could still be dispersed in nanometer size in the organic solvent of the N,N-dimethylformamide.The stable dispersion state could be maintained for more than 180 days.(2) Scanning electron microscopy showed that when the content of the graft-modified nano-hydroxyapatite in the composite was 10% and 30%,an excellent nano-level dispersion effect exhibited.When the content was 50%,the modified nano-hydroxyapatite could not be uniformly dispersed in the poly lactic acid system.(3) With the increase of graft-modified nano-hydroxyapatite content,tensile strength decreased and elastic modulus increased.The results showed that graft-modified nano-hydroxyapatite content in the composite had better mechanical properties when the content was 10%.(4) CCK-8 assay results displayed that the composites of amino-grafted nanohydroxyapatite(10% content) and polylactic acid have no obvious toxicity to mouse fibroblasts.(5) It is concluded that the composites of amino-grafted nanohydroxyapatite(10% content) and polylactic acid have good mechanical properties and cytocompatibility.