【作者】 胡晓炜；

【导师】 毛昌杰；

【作者基本信息】 安徽大学 ， 分析化学， 2013， 硕士

【摘要】 石墨烯片层与片层之间有较强的范德华力,很容易因此产生聚集,使其难溶于水及常用的有机溶剂,这就给石墨烯的进一步应用造成了非常大之困难。氧化石墨烯/聚苯胺复合物作为一种功能化的石墨烯,与石墨烯相比,具有更好的水溶性,优异的电学、光学等物理和化学性质,在生物传感器、纳米电子器件、复合材料、能量储存和转换、生物科学与技术等领域得到了广泛的应用。本文致力于基于石墨烯/聚苯胺纳米复合材料的新型生物传感器,提高分析的灵敏度。将纳米技术、电分析技术和生物技术有机结合起来,着重围绕纳米复合材料的制备及其在生物分析中的应用开展研究。主要研究内容如下：1、氧化石墨烯/聚苯胺/硒化镉量子点纳米复合物的合成及其电致化学发光生物传感器将氧化石墨烯/聚苯胺复合物与硒化镉量子点复合,增强了硒化镉量子点的ECL。实验采用层层组装技术制备了基于氧化石墨烯/聚苯胺/硒化镉(GO/PANi/CdSe QDs)纳米复合物的ECL生物传感器,测试结果表明,该传感器具有较高且稳定的电致化学发光强度、良好的生物相容性；该传感器灵敏度高、选择性好,其线性范围为0.05～100μM,检测限为0.02μM。该传感器在生物分析和环境检测等方面具有潜在的应用价值。2、氧化石墨烯/聚苯胺纳米线阵列/硒化镉量子点复合物合成及其电致化学发光免疫传感器我们合成了一种新颖的氧化石墨烯/聚苯胺纳米线阵列/硒化镉量子点复合物,作为复合探针对human IL-6进行了电致化学发光免疫分析。首先,通过一步合成法制备获得GO/PANi纳米线阵列复合物,使之与硒化镉量子点复合制得形貌均一生物GO/PANi/CdSe QDs纳米复合物,这种纳米复合物具有较大的比表面积和良好的生物相容性。并将该复合材料与抗体分子通过交联法结合,形成复合生物探针,发展了一种可用于检测Human IL-6的电致化学发光免疫传感器。该免疫传感器对Human IL-6具有高灵敏性和选择性,其检测范围为0.0005～10ng/mL,检测限为0.17pg/mL。该方法有望应用于临床诊断以及生物分析体系等领域。3、氧化石墨烯/聚苯胺复合材料的合成及其电化学生物传感器我们构建了一种基子氧化石墨烯/聚苯胺纳米线阵列复合材料的电化学生物传感器。通过Hummers法制备氧化石墨烯(GO),以过硫酸钾(K2S2O8)为氧化剂将苯胺单体聚合在氧化石墨烯表面,得到具有良好生物相容性、水溶性以及较大比表面积的GO/PANi纳米复合材料,用于构建对多巴胺的电化学生物传感器。结果表明,该生物传感器对多巴胺显示出灵敏、快速的响应,响应的线性范围为1.0×10-8M～1.0×10-5M,检测限为1.02×10-9M。该电化学生物传感器响应速度快、稳定性好,在生物分析中具有很大的应用潜力。更多还原

【Abstract】 The poor dispersion of graphene nanosheets, which results from Van der Wals forces between layer and layer in graphene, is of crucial importance for their applications. Graphene Oxide/Polyaniline (GO/PANi) nanocomposites, one kind of the functionalized graphene, have excellent electrical, optical and other physical and chemical properties, It has been demonstrated that Graphene Oxide/Polyaniline (GO/PANi) nanocomposites have been widely studied in the area of sensors, nanoelectronic devices, energy storage and conversion, bioscience and technology.This dissertation focuses on the studies on the biosensor based on the GO/PANi nanocomposite with the combination of nanotechnology, analytical chemistry, and biotechnology.Main work as follows:1. Fabrication of GO/PANi/CdSe Nanocomposites for Sensitive Electrochemiluminescence BiosensorA novel graphene oxide sheets/polyaniline/CdSe quantum dots (GO/PANi/CdSe) nanocomposites were successfully synthesized and used for the sensitive electrochemiluminescence (ECL) biosensing. The GO/PANi/CdSe nanocomposites were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), ultraviolet-visible (UV-vis) absorption spectroscopy, photoluminescence (PL) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Finally, the nanocomposites were employed to construct the biosensor via layer-by-layer assembly for the ECL detection of Cytochrome C (Cyt C). The whole process was characterized by cyclic voltammogram (CV) and electrochemical impedance spectroscopy (EIS). Experimental parameters such as the ratio of GO/PANi, the K2S4O8concentration and the pH value of electrolyte solution were studied to investigate the effect on the ECL intensity. Under the optimized conditions, the ECL intensity decreased linearly with the Cyt C concentrations in the range from5.0×10-8to1.0×10-4M with detection limit of2.0×10-8M. Besides, the as-proposed biosensor exhibits high specificity, good reproducibility, and stability, and may applied in more bioanalytical systems.2. Electrochemiluminescence immunosensor based on graphene oxide nanosheets/polyaniline nanowires/CdSe quantum dots nanocomposites for ultrasensitive determination of human interleukin-6A novel graphene oxide nanosheets/polyaniline nanowire arrays/CdSe quantum dots (GO/PANi/CdSe) nanocomposites is successfully synthesized and use as ECL immunosensor for detection of human interleukin-6(IL-6). The as-prepared GO/PANi/CdSe hybrid shows excellent biocompatibility, dispersity and solubility. Electrochemiluminescence (ECL) of CdSe quantum dots (QDs) was greatly enhanced by combining with GO/PANi nanocomposites. Herein, this hybrid was applied to develop an ultrasensitive ECL immunosensor for detection of IL-6. The ECL immunosensor has a sensitive response to IL-6in a linear range of0.0005-10ng mL-1with a detection limit of0.17pg mL-1. The ECL immunosensor exhibits high specificity, long-term stability and excellent reproducibility, which make it possible to be used in clinical application.3. Preparation and electrochemical biosensor of GO/PANi nanocompositesThe novel biosensor based on GO/PANi composites was successfully fabricated. Graphene oxide (GO) was prepared from graphite powder by a modified Hummers method. GO/PANi composites was synthesized by facile in-situ polymerization using GO and aniline monomer as the raw materials. The nanocomposites which showed large specific surface and good biocompatibility was used to construct the electrochemical biosensor of dopamine. The results show that the biosensor has high sensitivity and fast response for dopamine. The linear range of the biosensor to dopamine is from1.0×10-8M to1.×10-5M with the detection limit of1.02×10-9M. The biosensor prepared shows fast sense, high sensitivity, good stability and specificity and has broad potential application in bio-analysis.更多还原