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Creation of High Performance Biocompatible Surface by Surface modification agent which Constructs High Density Tethered Chains

通过构建高密度系链的表面改性剂创建高性能生物相容性表面

基本信息

批准号：
10558139
负责人：
NAGASAKI Yukio
金额：
$ 4.48万
依托单位：
SCIENCE UNIVERSITY OF TOKYO
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

We have synthesized seceral types of hydrophilic-hydrophobia block copolymers which forms supramolecular nanostructure in aqueous media due to the self-assembly of the block copolymers. For example, poly(ethylene glycol)/poly(lactide) block copolymer forms spherical core-shell type polymeric micelle in aqueous media, the size of which was 20-40 nm. The shell of the micelle was constructed by tethered PEG chains, whose density was very high in principle because of the thermodynamic balance.The objective of our study was to construct polymer micelle covered surface. If the surface was covered by spherical polymer micelles densely, the density of tethered chains should be much higher that conventional brushed chain surface.We prepared two types of polymer micelle. One of them is poly(2-hydroxyethyl methacrylate)-b-poly(alkylsilylstyrene) (HA) block copolymer micelle. By casting this polymer micelle on the substrate surface, the micelle adsorbed on the surface densely. Platelet adhesion to the modified surface was investigated. The adhesion on the HA-micelle modified surface was mush suppressed than that of not only native substrate but also poly(HEMA) surface. Entropy elastic effect of dense tethered chain may be the reason for this phenomena.Alternately, PEG/PLA block copolymers possessing aldehyde group at PEG chain end and methacryloyl group at PLA chain end was prepared. The block copolymer in aqueous media forms core shell type polymer micelle possessing aldehyde groups on the surface. The methacryloyl group in the core could be polymerized radically to form non dissociative micelle. To a primary-amino containing substrate surface, the aldehyde-micelle was modified covalently via reductive amination reaction. The obtained surface was very dence in polymer micelle and extremely high non-fouling character.These types of highly tethered chain surface was anticipating as new biocompatible surface modification agents.

我们合成了几种嵌段共聚物，它们在水溶液中通过自组装形成超分子纳米结构。例如，聚（乙二醇）/聚（丙交酯）嵌段共聚物在水介质中形成球形核-壳型聚合物胶束，其尺寸为20-40 nm。胶束的壳层由PEG链构成，由于热力学平衡，PEG链的密度很高。如果表面被球形聚合物胶束密集地覆盖，则拴系链的密度应该比常规刷状链表面高得多。其中之一是聚甲基丙烯酸2-羟乙酯-b-聚烷基硅基苯乙烯（HA）嵌段共聚物胶束。通过将该聚合物胶束浇铸在基底表面上，胶束密集地吸附在表面上。血小板粘附改性表面进行了研究。HA-胶束修饰的表面上的粘附不仅比天然基底而且也比聚（HEMA）表面的粘附受到更大的抑制。另外，我们还制备了PEG/PLA嵌段共聚物，PEG/PLA嵌段共聚物的末端含有醛基，PLA末端含有甲基丙烯酰基。该嵌段共聚物在水介质中形成表面带有醛基的核壳型聚合物胶束。核中的甲基丙烯酰基可自由基聚合形成非解离胶束。通过还原胺化反应将胶束共价修饰到含伯氨基的底物表面。所得表面具有高度的聚合物胶束密度和极高的抗污染性能，有望成为新型生物相容性表面改性剂。