Preparation and Function of Oriented Monolayers of Helical Peptides

建立了垂直取向螺旋肽自组装膜的制备方法。一种方法是使用硫辛酸及其衍生物作为螺旋肽与金表面之间的连接体，另一种方法是使用螺旋肽与氨基衍生化表面之间的双碱基形成。在任何一种情况下，螺旋肽都被设计成具有高度自组织能力。从三个方面对螺旋肽自组装膜的功能进行了研究。首先，在螺旋肽上沿着有序排列电子介导基团，研究了衍生化螺旋肽SAM作为电子介体的电子性质。螺旋肽SAM显示出阳极光电流，这表明由于发色团沿螺旋轴沿着有规律地间隔开而具有良好的电子介导性质。其次，制备了一种在C末端具有N-乙基咔唑基的螺旋肽SAM，并研究了其光电流产生。实现了具有较高量子效率的阳极光电流。第三，将疏水性螺旋肽与亲水性冠醚缀合。两亲性化合物在金表面形成了nm范围内的条带图案。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层的网络。PbS膜由于其介观尺度而表现出良好的介电性质。

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.