【作者】 庞少朋；

【导师】 计剑；

【作者基本信息】 浙江大学 ， 高分子材料， 2012， 硕士

【摘要】 本文以心血管植入材料的表面修饰为背景,利用具有细胞膜仿生特性的磷酸胆碱基团优异的生物相容性及阻抗蛋白质粘附性能,采用层层自组装方法,构建了含有磷酸胆碱基团的多层膜,分析了多层膜的稳定性,并探索了一些参数对组装过程的影响。基于Zr4+同磷酸基团的离子络合作用构建含磷酸胆碱的层层自组装多层膜体系研究首先用传统的自由基聚合方法成功的合成了含大量磷酸胆碱基团的聚合物聚-2-甲基丙烯酰氧基乙基磷酸胆碱酯(PMPC).利用四价锆离子(Zr4+)同磷酸根或磷酸酯基团间存在离子络合作用作为驱动力,成功地制备了PMPC多层膜——[PMPC/Zr4+]n多层膜。通过椭圆偏振光谱及石英晶体微天平的跟踪PMPC同Zr4+的层层自组装过程表明,多层膜的厚度及质量增长与双层膜数量的增长之间呈线性关系,[PMPC/Zr4+]n多层膜具有一定的可设计性。实验证明了[PMPC/Zr4+]n多层膜在PBS溶液中具有较好的稳定性。PMPC同Zr4+溶液的pH及浓度会对组装过程产生很大影响。[PMPC/Zr4+]n多层膜的抗蛋白质粘附实验证明了该多层膜修饰的表面具有优异的抗污性能。基于环氧氨基反应构建含磷酸胆碱的共价层层自组装多层膜研究进一步开发了基于环氧氨基反应构建含磷酸胆碱的共价层层自组装多层膜的体系。首先利用传统自由基聚合方法成功地制备了含有环氧基团的甲基丙烯酸环氧丙酯(GMA)及含有磷酸胆碱基团的2-甲基丙烯酰氧基乙基磷酸胆碱酯(MPC)的无规共聚物P(MPC-GMA)(MG),选用聚乙烯亚胺(PEI)(分子中含有大量伯胺基团)作为组装的另一组分同MG进行共价层层自组装。巧妙的利用交替旋涂层层自组装方法制备了[MG/PEI]n多层膜,椭圆偏振光谱及石英晶体微天平的跟踪MG同PEI的交替旋涂层层自组装过程表明,该组装的增长同双层膜膜数的增长呈线性关系,即多层膜具有一定的可设计性。实验证明了基于共价键交联的[MG/PEI]n多层膜在水及PBS溶液中具有长效的稳定性能。多层膜的组装驱动力为环氧氨基间的化学反应,因此还研究了组装在旋涂停止后的多层膜静置时间的影响。由于很多生物大分子都含有活性氨基基团,文章进一步考察了基于这种环氧氨基间的化学反应驱动力在制备生物大分子多层膜上的应用。更多还原

【Abstract】 Much attention has been paid to the surface-modification of the cardiovascular implant materials. Phosphorylcholine (PC) coatings have been fabricated via two different strategies by layer-by-layer self-assembly method.Layer by layer self-assembly of poly[2-(methacryloyloxy) ethyl phosphorylcholine] multilayer via the ionic complexation with zirconiumZirconium-phosphonate (Zr-P) ionic complexation chemistry is explored as a new approach to fabricate poly[2-(methacryloyloxy) ethyl phosphorylcholine](PMPC) multilayer film by layer-by-layer self-assembly method. Quartz crystal microbalance with dissipation (QCM-D) and optical ellipsometry measurements demonstrated that PMPC layer can be fully absorbed on each Zr4+layer. The thickness of the multilayer film with a good linear relationship was followed by the ellipsometry in situ adlayer characterization. The influence of pH of the PMPC and Zr4+solutions on the multilayer deposition were investigated by optical ellipsometry. QCM-D results indicated that the multilayer film is stable in a PBS flowing chamber at a high flow rate of5.2×10-3m/s. The ellipsometry data demonstrated that67.2%of the film still remained on the silicon wafer after being strong shaken in PBS at80rpm for12hours. The adsorption of bovine serum albumin (BSA) and fetal bovine serum (FBS) on the PMPC surface was monitored by the QCM-D and spectroscopic ellipsometry, and the results showed the multilayer film have excellent protein resistance.Covalently bonded layer-by-layer assembly of polymer multilayer film based on epoxy groupsThe covalent bond multilayer coating which contains PC has been formed based on the reaction of epoxy groups and primary amine groups. The layer by layer self-assembly of P(MPC-GMA)(MG) and PEI was carried out by spin coating method. The growth of the multilayer from MG and PEI was successfully traced by QCM-D and optical ellipsometry measurements. The thickness of the multilayer film with a linear relationship was followed by the ellipsometry in situ adlayer characterization. The multilayer films [MG/PEI]n were stable in PBS and water has been demonstrated by strong shaken in PBS and water at80rpm for80hours. The influence of reaction time of epoxy groups and primary amine groups was also carried out. Biomacromolecules also be used to layer by layer self-assembly with MG.更多还原