DNA超分子结构定位引导的聚苯胺纳米结构图案合成研究及其在对映选择催化和场效应晶体管传感器中的应用

The structures and functions of polyaniline nanomaterials have been hot topic in the field of conductive polymer in recent years. The construction of complex polyaniline nanopatterns with controllable morphologies in 1D, 2D or 3D space, still remains as a challenging subject. Based on self-assembly technique of DNA and the ability of spatial positioning of DNA nanostructures,as well as the feature of region-selective catalysis of enzymes, we will manage to establish the method to modulate the morphologies of polyaniline nanopattern on nanostructured DNA templates. In this proposal, horseradish peroxidase(HRP)-mimicking DNAzyme will be assembled onto DNA duplex backbone through base pairing, so that the DNAzyme will catalyze the polymerization of aniline on the DNA duplex as the counter-ions temlate. The synthesis conditions of emeraldine base (EB) form of polyaniline will be investigated, the mechanism of the templated polymerization will be revealed, and directed growth of polyaniline by 1D DNA nanostructure will be explored. As a basis, we will assemble HRP-mimicking DNAzyme on the DNA rectangular and tubular origami nanostructures,respectively, which will act as the template for the fabrication of polyaniline nanostructured patterns. The morphology and geometrical parameters of polyaniline nanopatterns on the template surface will be investigated by adjusting the spatial position and the distance of the DNAzyme sites, in addition to the polymerization conditions of aniline, and the relationship between the morphologies of the pattern and the optical activity, the electrical property will be studied. In addition, the 2D rectangluar template will be used for the growth of polyaniline nanostructures that will reach out of the template size. Due to controllable morphologies features, polyaniline patterns will be applied as the chiral recognition host for enzymatic enantioselective catalysis and the sensing element for field-effect transistor.

聚苯胺纳米材料结构与功能的研究是近些年来导电聚合物研究的热点。如何在一维至三维空间构建形态可控的聚苯胺纳米图案，仍是一项有挑战性的研究课题。我们将立足于DNA自组装技术和DNA纳米结构的空间定位功能，利用酶催化的区域选择特性，在DNA模板表面构建聚苯胺纳米图案，并建立其形态特征的调控方法。本项目拟通过DNA过氧化物模拟酶与DNA骨架的自组装，考察DNA模拟酶催化合成本征态聚苯胺的条件，揭示模板介导苯胺聚合的机理，以多种方式研究一维DNA结构对聚苯胺生长的定位能力。在此基础上，将DNA模拟酶组装到DNA折纸结构模板上，探索模拟酶间距、空间排列方式和苯胺聚合条件对聚苯胺纳米图案形态和几何参数的影响，寻求使聚苯胺结构体尺寸突破模板空间限制的可能，研究聚苯胺图案的形态特征与光学活性、电学性质的关系。我们也将形态可控的聚苯胺纳米图案用作酶对映选择性催化的手性识别主体和场效应晶体管的感应元件。

聚苯胺纳米材料结构与功能的研究是近些年来导电聚合物研究的热点；自掺杂聚苯胺纳米材料的合成在生物学领域具有重要的意义。如何在一维至三维空间构建形态可控的自掺杂聚苯胺纳米图案，仍是一项有挑战性的研究课题。本项目立足于DNA自组装技术和DNA纳米结构的空间定位功能，利用酶催化的区域选择性，在DNA模板表面，构建聚苯胺纳米图案，并探索形态特征的调控方法。通过DNA过氧化物模拟酶与DNA模板的自组装，催化合成了具有导电态结构的聚苯胺，并引导聚苯胺优先从酶位点生长，进而覆盖DNA模板表面；带有负电荷的DNA模板可为导电态的聚苯胺提供必要的反离子，使其在近中性和弱碱条件下被掺杂和脱掺杂。在此基础上，将DNA模拟酶组装于具有空间寻址功能的DNA折纸纳米结构表面；通过DNA模拟酶对聚苯胺生长的空间定位能力，控制聚苯胺合成的纳米图案形状严格按照DNA模拟酶的分布方式生长，并分析其区域可控合成的机理。这是首次关于在模板表面位置形状可控的导电高分子纳米材料的合成制备，也为复杂导电高分子图案和纳米电子学器件的制备提供了研究基础。