生物活性多糖及生物酶对医用聚乳酸材料表面修饰的研究

发布时间：2018-03-24 19:56

本文选题：香菇多糖　切入点：溶菌酶　出处：《武汉理工大学》2012年硕士论文

【摘要】：生物医用高分子材料是一类用来对生物体进行诊断、治疗或恢复损坏组织器官功能的高分子材料,近年来,可谓异军突起,成为发展最快的生物材料之一,对人类身体健康和社会发展具有越来越重要的影响。对于生物医用高分子材料而言,材料的生物性能不仅受到其自身性质的影响,而且在相当大的程度上还取决于材料表面的化学性质与物理性质。因此,为了改善材料的生物相容性能,对其表面进行一定的修饰是十分必要的。本研究首先从香菇子实体中提取香菇多糖,然后对其进行不同的衍生化修饰,最后采用不同的方法将香菇多糖衍生物以及其他生物大分子固定到聚乳酸生物材料表面,并对被修饰材料的表面性能和生物性能进行了表征和分析,具体如下：研究了采用化学接枝方法利用共价键将羧甲基香菇多糖固定在氨基化聚乳酸基材表面,得到羧甲基香菇多糖化学接枝修饰的聚乳酸材料。此外,通过在氨基化聚乳酸基材表面进行羧甲基香菇多糖与壳聚糖的层层自组装,得到生物多糖层层自组装修饰的聚乳酸材料。采用扫描电子显微镜、水接触角测量仪、抗菌活性测试、溶血试验和血栓试验等方法对被修饰聚乳酸材料的表面性能和生物性能进行了分析和比较。结果表明采用两种表面修饰方法得到的羧甲基香菇多糖修饰的聚乳酸材料的亲水性、血液相容性以及对大肠杆菌抗菌活性得到改善。与化学接枝方法相比,经过羧甲基香菇多糖与壳聚糖层层自组装修饰的聚乳酸材料具有更好的亲水性、血液相容性和抗菌活性。研究了采用层层自组装技术将溶菌酶和香菇多糖硫酸酯固定到氨基化聚乳酸基材表面。测试结果表明,表面修饰后的聚乳酸材料亲水性得到了改善；血小板粘附测试和溶血试验说明,被修饰材料具有了良好的血液相容性能,其表面血小板粘附数量相比未修饰材料有了明显减少,溶血率也有所降低；抗菌活性测试表明,修饰后的聚乳酸材料对大肠杆菌和金黄色葡萄球菌显示出了良好的抑制效果,其抑菌率分别提高了41.7%和67.8%。本研究选择具有生物活性的香菇多糖衍生物以及特殊抗菌性能的溶菌酶作为表面修饰医用高分子材料的活性物质,通过不同的方法对材料的表面微观结构以及化学组成进行改性,从而赋予被修饰材料溶菌酶以及香菇多糖衍生物所具有的特殊生物活性。本研究也将为制备生物活性大分子(如,生物多糖、蛋自质和酶)表面修饰的医用高分子材料提供一种新的思路。
[Abstract]:Biomedical polymer material is a kind of polymer material used to diagnose, treat or restore the function of damaged tissues and organs. In recent years, it has become one of the fastest-growing biomaterials. It has more and more important influence on human health and social development. For biomedical polymer materials, their biological properties are affected not only by their own properties, but also by the chemical and physical properties of their surfaces to a considerable extent. In order to improve the biocompatibility of the material, it is necessary to modify its surface. In this study, lentinan was extracted from the fruiting body of Lentinus edodes and then modified with different derivatives. Finally, Lentinan derivatives and other biological macromolecules were immobilized on the surface of polylactic acid biomaterials by different methods, and the surface and biological properties of the modified materials were characterized and analyzed, as follows:. The chemical grafting method was used to immobilize carboxymethyl lentinan onto the surface of amino polylactic acid base material by covalent bond, and the modified polylactic acid material was obtained by chemical grafting of carboxymethyl lentinan. A layer by layer self-assembly of carboxymethyl lentinan and chitosan was carried out on the surface of amino polylactic acid substrate to obtain the self-assembled and modified polylactic acid material with biological polysaccharides, which was modified by scanning electron microscope (SEM) and water contact angle measuring instrument. Antimicrobial activity test, The surface and biological properties of the modified polylactic acid materials were analyzed and compared by hemolysis test and thrombus test. The results showed that the hydrophilic properties of the modified poly (lactic acid) materials modified by carboxymethyl lentinan were obtained by two surface modification methods. Compared with the chemical grafting method, the modified poly (lactic acid) material modified by layers of carboxymethyl lentinan and chitosan had better hydrophilicity, blood compatibility and antibacterial activity. The layer by layer self-assembly technique was used to immobilize lysozyme and lentinan sulfate onto the surface of amino polylactic acid substrate. The results showed that the hydrophilicity of the modified PLA material was improved. Platelet adhesion test and hemolysis test showed that the modified material had good blood compatibility, the platelet adhesion number on the surface of the modified material was significantly lower than that of the unmodified material, the hemolysis rate was also decreased, and the antibacterial activity test showed that, The modified poly (lactic acid) showed a good inhibitory effect on Escherichia coli and Staphylococcus aureus, and its bacteriostatic rate increased by 41.7% and 67.8%, respectively. In this study, bioactive shiitake mushroom polysaccharide derivatives and lysozyme with special antibacterial properties were selected as active substances for surface modification of medical polymeric materials. The surface microstructure and chemical composition of the material were modified by different methods. So that the modified material lysozyme and lentinan derivatives have special biological activities. This study will also be used for the preparation of bioactive macromolecules (for example, biopolysaccharide, Lentinus edodes, Lentinus edodes). The surface modification of egg and enzyme provides a new idea for medical polymer materials.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

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