表面硅烷修饰的AEXCB-β-TCP/PLGA双相可控降解骨修复支架材料研究

The degradation rate of the scaffold material does not match that of the restoration of bone tissue, which is one of the most serious challenges in the promotion of tissue engineering technology in clinical use. The project aims to constructing a new inorganic-polymeric composite scaffold materials for bone repairing through which the degradation of the restoration scaffold materal is double controllable, the rate of degradation matches that of the bone heal and the complete degradation is under control between 4 to 12 months. Inorganic phases are composed of antigen-extracted xenogeneic cancellous bone（AEXCB）and β-tricalcium phosphate (β-TCP),while polymer of poly(lactic-co-glycolic acid)（PLGA）. The degredation rate of β-TCP will be lowered with the addition of AACB.The cancellous bone of scaffold material and the degredation rate of β-TCP make gradient change with the variation of the particle size and contents of inorganic phase.The controlling scope of degradation rate can be extended by adjusting the change of PLGA molecular weight and component concentration so as to meet the demand of duplex controllable degradation. The interface reactions between inorganic elements and polymer interface will be effectively resolved by constructing a nanoscale silicane modifying layer on the surface of AEXCB-β-TCP.The degradation mechanism of the composite scaffold materials in vitro and in vivo and the function mechanism of the silicane modifying layer will be investigated to offer theoretical basis for material design.

组织工程支架材料的降解速率与新生骨组织的生长速率不匹配，是目前骨组织工程技术向临床应用推进过程中面临的重要挑战之一。本课题创造性地构建了一类新型的无机/高分子复合双可控降解的骨组织修复支架材料，降解速率与骨愈合速率匹配，完全降解在4-12个月之间可调可控。无机相由去抗原异种松质骨(AEXCB)和β-磷酸钙(β-TCP)组成，高分子则由聚丙乙交酯（PLGA）组成。通过在复合体系中添加AACB来调控β-TCP过快的降解速率，并通过无机相粒径与含量的变化，实现AEXCB和β-TCP降解速率的梯度变化；通过控制PLGA分子量和组分含量的变化，继续扩大材料降解速率的可控范围，实现复合体系的双相可控降解。在AEXCB-β-TCP表面创建纳米级硅烷修饰层，有效解决无机相与高分子界面作用问题。对复合支架材料在体内外的降解机理和硅烷修饰层的作用机理进行研究，为材料设计提供理论依据。

组织工程支架材料的降解速率与新生骨组织的生长速率不匹配，是目前骨组织工程技术向临床应用推进过程中面临的重要挑战之一。本项目旨在通过构建无机/高分子复合双相可控降解支架体系，使复合支架材料的降解速率与骨愈合速率匹配，以满足软骨和松质骨等非承载部位骨缺损修复的临床需要。在国家自然科学基金委科学部主任基金的支持下，本项目圆满地完成了预期研究任务，取得了预期研究成果。课题组创造性地构建了一类新型的无机/高分子复合双可控降解的骨组织修复支架材料，降解速率与骨愈合速率匹配，完全降解在4-12 个月之间可调可控。无机相由去抗原异种松质骨(AEXCB)和β-磷酸钙(β-TCP)组成，高分子则由聚丙乙交酯（PLGA）组成。通过在复合体系中添加AACB 来调控β -TCP 过快的降解速率，并通过无机相粒径与含量的变化，实现AEXCB 和β -TCP 降解速率的梯度变化；通过控制PLGA 分子量和组分含量的变化，继续扩大材料降解速率的可控范围，实现复合体系的双相可控降解。在AEXCB-β-TCP 表面创建纳米级硅烷修饰层，有效解决无机相与高分子界面作用问题。对复合支架材料在体内外的降解机理和硅烷修饰层的作用机理进行研究，为材料设计提供理论依据。在本项目的资助下，项目组取得了如下的研究成果：（1）在《Polymers & Polymer Composites》、《Polymer-Plastics Technology and Engineering》、《Journal of Macromolecular Science, Part B: Physics》、《Journal of Macromolecular Science, Part A: Pure and Applied Chemistry》、《Ceramics International》、《Vacuum》、《Ionics》、《Applied Surface Science》、《Journal of Power Sourcesl》等刊物上发表了13篇，其中会议论文3篇，被SCI/EI收录10篇。（2）申请国家发明专利1项；（3）培养硕士研究生5名。