蛋白质表面分子印迹自组装膜的构筑及其传感性能

项目名称： 蛋白质表面分子印迹自组装膜的构筑及其传感性能

项目编号： No.20873062

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 生物科学

项目作者： 杜学忠

作者单位： 南京大学

项目金额： 32万元

中文摘要： 纳米技术与生物技术结合用于纳米生物检测与传感，是近年来的热门研究领域。本项目利用多种自组装技术，引入功能纳米粒子，构筑具有多重作用位点特异性结合蛋白的自组装膜。通过金属配位，富含组氨酸蛋白与亚胺二乙酸功能化自组装单层膜修饰纳米金特异性结合，形成夹心型结构，利用纳米金显色检测蛋白，发现与蛋白表面组氨酸残基数目、间距以及蛋白尺寸紧密相关。在高醇水比例溶剂体系中一步制备稳定的银核二氧化硅壳表面增强拉曼散射标记物纳米粒子及其与纳米金复合粒子，通过亚胺二乙酸功能化自组装单层膜固体基片，高灵敏特异性检测共价偶联及溶液中自由态富含组氨酸蛋白，表明选择适当配体，该方法可用于其它种类蛋白及生物分子检测，具有普适性。通过层层自组装，阴离子葡聚糖包裹金纳米棒，降低表面活性剂生物毒性，同时特异性结合伴刀豆球蛋白，原位实时及光学检测蛋白识别。制备固载血红蛋白的壳聚糖功能化石墨烯薄膜，实现过氧化氢和亚硝酸根高灵敏和宽范围的电催化检测。葫芦脲准轮烷自组装单层膜构筑在（磁性）介孔二氧化硅纳米粒子表面形成超分子纳米阀，该体系具有酸碱、竞争结合以及生物酶引发的控制释放性能，在生物传感及体内靶向给药方面具有潜在的应用前景。

中文关键词： 蛋白特异性结合；功能纳米粒子；自组装膜；识别与检测；控制释放

英文摘要： Nano-bioassay and biosensing in combination of nanotechnology and biotechnology have become hot research fields recently. In this project, protein-specifically bound thin films with multivalent binding sites in combination of functionalized nanoparticles have been fabricated through different self-assembly technologies. Specific binding of histidine (His)-rich proteins to iminodiacetic acid (IDA)-functionalized gold nanoparticles through metal coordination formed sandwiched structures. Protein detections were achieved by colorimetric observations and UV-vis spectral measurements. It is found that the optical sensing of His-rich proteins is closely related to number and distribution of surface His residues as well as size of proteins. Stable surface enhanced Raman scattering (SERS) tags of silver core-silica shell nanoparticles and composites with gold nanoparticles were prepared in the mixed solvent with a high volume ratio of ethanol to water without vitreophilic pretreatment. Covalently coupled and free His-rich proteins could be sensitively detected through metal coordination with IDA-functionalized wafers (self-assembled monolayers) using the core-shell SERS tags. It is clear that the synthesized core-shell SERS tags can be applied for assays of other proteins or biomolecules if corresponding specific ligands are used and have potential application in immunoassays. Binding of dextran sulfate sodium to CTAB-coated gold nanorods using layer-by-layer self-assembly were studied by means of quartz crystal microbalance with dissipation (QCM-D) in real time and UV-vis spectra not only for minimization of CTAB toxicity but also for specific binding of concanavalin A. Biosensors of hemoglobin-immobilized composite films of chitosan-functionalized graphene were constructed for electrochemical detections of hydrogen peroxide and nitrite both in high sensitivity and in wide concentration range. The supramolecular nanovalves of cucurbituril pseudorotaxanes using (magnetic) mesoporous silica nanoparticles were constructed, and their controlled releases were driven by pH activation, competitive binding, and enzyme inspiration. The delivery systems have promising applications for biosensors and in vivo site-specific drug release.

英文关键词： specifical protein binding; functionalized nanoparticles; self-assembled films; recognition and detection; controlled release