【作者】 马超；

【导师】 黄鑫；

【作者基本信息】 哈尔滨工业大学 ， 化学工程（专业学位）， 2017， 硕士

【摘要】 近年来,聚合诱导自组装技术的发展已经成为合成嵌段共聚物纳米材料的一种通用方法,其可以在高聚合物浓度下进行反应。而蛋白质自组装纳米材料由于其生物相容性、降解性极好和丰富的功能性,以及在药物/基因运输,蛋白质治疗,纳米反应器或人造细胞等领域中的广泛应用,同样受到了越来越多的关注。考虑到蛋白质结构十分脆弱,在传统聚合诱导自组装方法那种高温的条件下很难进行反应,因此研究聚合诱导蛋白质自组装是十分有意义的。在本文中,我们展示了一种简单有效地合成蛋白质纳米粒子的方法,通过使用多位点RAFT试剂修饰的牛血清白蛋白(BSA)作为大分子链转移剂,利用光引发的RAFT聚合诱导自组装。1、合成一种基于牛血清白蛋白的大分子链转移剂(BSA-CTA)。我们设计合成一种巯基噻唑啉酯活化的RAFT试剂,利用BSA表面的氨基和噻唑啉酯在H2O/DMSO两相界面进行反应,合成BSA-CTA链转移剂。通过紫外吸收光谱和基质辅助激光解吸电离飞行时间质谱来计算出BSA表面的RAFT试剂数量。2、通过光引发RAFT聚合诱导实现了BSA原位自组装,得到球形蛋白质纳米粒子。通过扫描电子显微镜、透射电子显微镜、动态光散射仪和凝胶渗透色谱等方法对自组装纳米粒子的形貌、尺寸和聚合物分子量和分子量分布(PDI)进行分析。而且在改变实验条件下,依然能够稳定的得到球形纳米粒子,纳米粒子的尺寸在164 nm-255 nm。3、探究了聚合诱导牛血清白蛋白自组装的机理。聚甲基丙烯酸羟丙酯(PHPMA)的链增长导致星型BSA-PHPMA耦合体的疏水性的增加,当达到溶液的临界聚集浓度时,它们将通过PHPMA间相互的疏水作用聚集成纳米粒子。4、我们验证了合成的BSA球形纳米粒子的稳定性、低细胞毒性和高酶活性。并通过封装作用实现了不同类型物质的包载,包括荧光染料尼罗红,小分子药物DOX和生物大分子DNA。更多还原

【Abstract】 In recent years,the development of polymerization-induced self-assembly(PISA)technology has become a versatile,one-pot strategy to synthesize block copolymer nanomaterials,which conducted at high polymer concentrations.However,protein-based self-assembled nano-objects have attracted much attention due to their great biocompatibility and degradability as well as highly sophisticated functions which have showed broad applications in drug/gene delivery,protein theraphy,nanoreactors,or artificial cells etc.Considering the very fragile structure of the protein,it is difficult to carry out the reaction at high temperature in the traditional PISA method.Therefore,it is very meaningful to study the PISA of proteins.In this study,we show a facile and efficient way to synthesize protein-based nanoparticles by taking advantage of photo-initiated RAFT polymerization induced self-assembly by using multi-RAFT modified bovine serum albumin(BSA)as a macro-RAFT agent.1.Synthesis of a macromolecule chain transfer agent based on bovine serum albumin(BSA-CTA).We designed and synthesized a mercaptothiazoline-activated RAFT agent,and then synthesized BSA-CTA by reacting the amino groups on the surface of BSA with mercaptothiazoline at the H2O/DMSO interface.And we calculated the number of RAFT agent on the surface of BSA via UV-vis spectroscopy and MALDI-TOF MS.2.The self-assembly of BSA was achieved via in-situ photoinitiated polymerization induced self-assembly to obtain spherical protein nanoparticles.And the morphology and size of nanoparticles,the molecular of polymer and polymer dispersity index(PDI)were analyzed by SEM,TEM,DLS and GPC.Under different experimental conditions,we still can obtain sphere nanoparticles with the size of 164-255 nm.3.The mechanism of polymerization-induced self-assembly of BSA was explored.The growth of the PHPMA chains results in the increase of the hydrophobicity of the star BSA-PHPMA conjugates,and when reaching the critical aggregation concentration in aqueous solution,they will aggregate into nanoparticles via the hydrophobic interaction of PHPMA.4.We confirmed the stability,low cytotoxicity and high enzyme activity of BSA sphere nanoparticles.And through the encapsulation effect to achieve the load of different types of substances,including fluorescence dyes Nile red,small molecule drugs DOX and biomacromolecules DNA.更多还原