分子自组装纳米止血材料的构筑过程及功效研究

The molecular self-assembly techniques is one of the hot technologies at nano-materials synthesis in recent years. Meanwhile, modern physical technologies such as scan probe microscopy (SPM), quartz crystal microbalance (QCM) technology provide potentiality for the nano-dimension resolution of materials. This topic focus on the natural organic macromolecules of chitosan and sodium alginate, and the main study includes the building process of this pair of polyelectrolyte self-assembled materials and its antibacterial, hemostatic efficacy. Firstly, polysaccharides with strong hemostatic activity are extracted from new sources and selected. Then, the thickness controllable hemostatic nano-materials are synthesised through spin coating assisted layer by layer self-assembly (LbL）of these two organic macromolecules. The assembly theory is studied by the micro-analysis of dynamic build process with AFM, QCM. And the hemostatic molecular mechanism will be explained following the study of interactions among material, plasma proteins and blood cells. Simultaneously, the evaluation of material properties and process optimization will be carried out to obtain efficient and safe new hemostatic nano-materials. Eventually, the hemostatic efficacy and safety of the nano-materials will be evaluated both in vitro and in vivo. The development of organic functional maromolecules from new sources and the nanotechnology provide this new hemostatic material with high viscosity and absorbency, which is expected to make up for the vacancy of the organ and the surface irregular bleeding treatment. In addition, the introduction of nanotechnology and the interface/surface in this study might provide a new understanding of the organic macromolecules function, molecular self-assembly mechanism, and the application of nanotechnology in the new biomedical materials.

分子自组装技术是近年国际上纳米材料合成的热点技术，SPM、QCM等现代物理技术的出现为材料的纳米级分辨提供了可能。本课题着眼于天然有机高分子壳聚糖和海藻酸钠，侧重研究这对聚电解质自组装材料的构筑过程及抗菌、止血功效。课题利用新来源强止血活性的高分子多糖原料，经旋涂辅助的逐层分子自组装构建厚度可控的纳米止血材料，AFM、QCM等微观解析材料动态构筑过程、与血浆蛋白和血细胞等的相互作用，从而在纳米水平上提供组装理论依据和阐述止血分子机制；同时评测材料性能和优化工艺获得高效、安全的新型纳米止血材料，并对其体内外止血疗效、安全性等进行研究。新来源有机功能分子的开发和纳米工艺赋予了新型止血材料高黏度和可吸收性，其有望弥补目前脏器和体表不规则区出血治疗的这一空缺，而纳米技术和界面/表面的引入也为深入理解自然界中有机高分子功能、分子自组装机理、以及纳米科技在新型生物医学材料的应用提供一个新的认识。

分子自组装是近年纳米材料合成的热点技术。本课题着眼于天然有机高分子壳聚糖和海藻酸钠，侧重研究这对聚电解质自组装材料的构筑及止血等功效研究。课题利用新来源强止血活性的高分子多糖原料，经旋涂辅助的逐层分子自组装构建厚度可控的纳米止血材料，SPM等微观解析材料结构以及与血细胞的相互作用；同时研究材料物理化学性能和优化合成工艺，以获得高效、安全的新型纳米止血材料，并对其体内外止血疗效、安全性等进行研究。本课题已提取新来源的止血原料4种，建立了一套新型分子自组装纳米复合止血材料合成新技术，制备出多个规格新型纳米复合材料。新来源有机功能分子的开发和纳米工艺赋予了新型分子自组装纳米复合止血材料高黏度、轻薄透明等特点。研究表明，新型分子自组装纳米复合止血材料无细胞毒性、无致敏、无刺激性，在大鼠肝损伤出血模型、小鼠深Ⅱ度烧烫伤模型上有良好的止血与促创伤愈合功效，有望弥补目前脏器和体表不规则区出血治疗的这一空缺；而纳米分子自组装技术及多糖高分子的引入也为新型生物医学材料的开发与应用提供新思路。