Preparation and Function of Oriented Monolayers of Helical Peptides

建立了垂直取向螺旋肽自组装单层膜（SAM）的制备方法。一种方法是利用硫辛酸及其衍生物作为螺旋肽与金表面的连接剂，另一种方法是利用螺旋肽与氨基衍生表面之间的席夫碱形成。在这两种情况下，螺旋肽被设计为具有高度的自组织能力。本文从三个方面研究了螺旋肽SAMs的功能。首先，在螺旋肽上有规则地排列电子中介基团，研究衍生螺旋肽SAM作为电子中介的电子性质。螺旋肽SAM表现出阳极光电流，由于其发色团沿螺旋轴有规则的间距，表明其具有良好的电子中介性能。其次，制备了C端含有n -乙基咔唑基的螺旋状肽SAM，并对其光电流产生进行了研究。以较高的量子效率实现了阳极光电流。第三，将疏水螺旋肽与亲水性冠醚偶联。两亲性化合物在金表面形成纳米范围内的条形图案。有趣的是，通过使用两亲性化合物的单层作为支架，获得了具有原子厚度的PbS层网络。由于其介观尺度，PbS膜表现出半导体性质。

The preparative methods for vertically oriented helical peptide self-assembled monolayers (SAM) were established. One way is to use lipoic acid and its derivative as a linker between helical peptides and gold surface, and the other is to use schiff-base formation between helical peptides and amino-derivatized surface. In either case, helical peptides are designed to be endowed with highly self-organizing potency. The functions of the helical peptide SAMs have been investigated in terms of three aspects. Firstly, electron mediating groups were regularly arranged along the helical peptide, and the electronic property of the derivatized helical peptide SAM as the electron mediator was studied. The helical peptide SAM showed an anodic photocurrent, suggesting a good electron mediating property due to regularly spacing chromophores along the helix axis. Secondly, a helical peptide SAM having an N-ethylcarbazolyl group at the C terminal was prepared, and the photocurrent generation was studied. An anodic photocurrent was realized with a relatively high quantum efficiency. Thirdly, a hydrophobic helical peptide was conjugated with a hydrophilic crown ether. The amphiphilic compound formed a strip-pattern in a nm-range on gold surface. Interestingly, a network of PbS layer with an atomic thickness was obtained by using the monolayer of the amphiphilic compound as a scaffold. The PbS membrane showed a semiconductive property due to its mesoscopic scale.