Supramolecular Porphyrin Based Catalysts and Sensors

本研究的重点是设计适合于在细胞色素c氧化酶活性中心模拟氧的四电子催化还原为水的非共价连接的超分子卟啉配合物，以及开发新型高效的检测氧的电化学传感器。为了实现这一目标，我们提出了设计、合成和研究离子对卟啉二聚体以及含钴卟啉的环糊精缩聚聚合物膜的超分子络合物。用离子对卟啉二聚体修饰的电极作为细胞色素C氧化酶活性中心的模型，在生理pH条件下将氧气直接四电子还原为水。通过在外围取代基上带有不同电荷的水溶性卟啉制备同核卟啉二聚体，如Co-Co、Fe-Fe或Mn-Mn。平面或非平面环的卟啉将被用来调节二聚体的环间距离。用环糊精钴卟啉缩合聚合物膜的超分子络合物修饰的电极将被设计成测定溶液中二氧化氧的传感器。无论是中性的环糊精聚合物，还是阴离子的，即羧甲基化的环糊精聚合物，都将被设计和制造成薄膜修饰电极，以在环的外围承载带有中性、阴离子或阳离子电荷的钴卟啉。通过使用各种电分析和光谱技术，我们首先将重点放在基础上，例如，所研究过程的机理和动力学方面。用离子对二聚体和环糊精的超分子络合物修饰的常规微电极随后将被制造出来。然后，这些电极将接受专用应用的测试。

The present research proposal is focused on designing non-covalently linked supramolecular porphyrin complexes suitable for mimicking the four-electron catalytic reduction of dioxygen to water at the active site of cytochrome c oxidase, and, also to develop new and efficient electrochemical sensors for dioxygen detection. Towards this goal, we propose to design, synthesize, and study ion-pair porphyrin dimers as well as supramolecular complexes of condensation polymer films of cyclodextrins hosting cobaltporphyrins. The electrodes modified with ion-pair porphyrin dimers are targeted as models for the active site of cytochrome c oxidase to perform a direct four-electron reduction of dioxygen to water at physiological pH conditions. Homonuclear porphyrin dimers, such as Co-Co, Fe-Fe or Mn-Mn will be prepared by using water soluble porphyrins bearing different charges on peripheral substituents. Either porphyrin of planar or non-planar rings will be utilized to adjust the inter-ring distance of a dimer. The electrodes modified with supramolecular complexes of condensation polymer films of cyclodextrin hosting cobaltporphyrins will be designed to serve as sensors for determination of dioxygen in solution. Both the neutral cyclodextrin polymer or anionic, i.e., carboxymethylated cyclodextrin polymer, film modified electrodes will be designed and fabricated to host cobaltporphyrins bearing either neutral, anionic or cationic charges on the ring periphery. By using various electroanalytical and spectroscopic techniques, first, we will focus on fundamental, e.g., mechanistic and kinetic aspects of the studied process. Conventional microelectrodes modified with supramolecular complexes of ion-pair dimers and cyclodextrins will subsequently be fabricated. Then, these electrodes will be tested for dedicated applications.