Mechanistic Studies of Photoinduced Electron Transport across Vesicle Bilayers

光诱导电子跨囊泡双层传输的机理研究

基本信息

批准号：
16550030
负责人：
MURATA Shigeru
金额：
$ 2.24万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

项目摘要

Endoergic electron transport across vesicle bilayers from ascorbate (Asc^-) in the inner waterpool to methylviologen (MV^<2+>) in the outer aqueous solution was driven by the irradiation of pyrene derivatives embedded in the vesicle bilayers. The initial rate of MV^<2+> reduction is dependent on the substituent group on the pyrenyl ring ; a hydrophilic functional group linked with the pyrenyl ring by a short methylene chain acts as a sensitizer for the electron transport. Mechanistic studies suggests that the electron transport is mainly initiated by the reductive quenching of the singlet excited state of pyrene by Asc^- and proceeds by a mechanism involving electron exchange between the pyrenes located at the inner and outer interface across the vesicle bilayer. Novel unsymmetrically substituted pyrenes having both a hydrophilic group linked by a short methylene chain and a hydrophobic long alkyl group was designed and synthesized, which acted as an excellent sensitizers for the electron transport across vesicle bilayers. Moreover, in order to enhance the electron transport efficiency, the effects of molecular structure of lipids and electron donors incorporated in the inner waterpool on the MV^<2+> reduction rate were investigated. The use of newly synthesized dimeric pyrenes bridged by a long alkyl chain as sensitizers resulted in the enhancement of electron transport efficiency. Although these systems unfortunately cannot work using visible light, it appears to be one of the most faithful model of natural photosynthesis in that an electron is transferred with the aid of light energy between two reversible redox couples in the energetically uphill direction through lipid bilayer walls preventing a charge recombination.

内部水池中从抗坏血酸（ASC^ - ）跨囊泡双层到甲基化学剂（MV^<2+>）的内部能力性电子传输是由嵌入在囊泡双层中的pyrene衍生物的辐射来驱动的。 MV^<2+>降低的初始速率取决于牙肾上环上的取代基；通过短甲基链与牙合环连接的亲水官能团充当电子传输的敏化器。机械研究表明，电子传输主要是通过ASC^ - 通过ASC^ - pyrene的单重激发状态的淬火引发的，并通过涉及在内部和外部界面横穿囊泡双层的Pyrenes之间进行电子交换的机制进行。设计和合成了新型的无亲水组和疏水性长烷基基团的亲水基团的新型无亲水组，并合成了疏水性长烷基基团，这是对跨囊泡双层的电子传输的出色敏感性。此外，为了提高电子传输效率，研究了内池中掺入MV^<2+>降低速率的脂质和电子供体的分子结构的影响。用长烷基链桥接的新合成的二聚体作为敏化剂，从而提高了电子传输效率。尽管不幸的是，这些系统无法使用可见光来工作，但它似乎是自然光合作用的最忠实的模型之一，因为电子通过脂质双层壁通过脂质双层壁沿着两个可逆的氧化还原夫妇之间的光能转移，从而可以通过脂质的双层壁悬挂，从而阻止了电荷重组。

项目成果

期刊论文数量（24）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Amphiphilic Pyranines : Chromophore Wrapped in a Hydrophobic Alkyl Chain and Micelle Formation Induced by Complexation with MV^<2+>

两亲性吡喃：发色团包裹在疏水性烷基链中，并通过与 MV^<2 > 络合诱导形成胶束

DOI：
发表时间：
2007
期刊：
Chemistry Letters 36・3
影响因子：
0
作者：
A.F.M.Mustafizur Rahman;T.Murafuji;K.Kurotobi;Y.Sugihara;N.Azuma;A.F.M.Musutafizur Rahman 他;A.F.M.Musutafizur Rahman 他;Gaku Yamamoto;Gaku Yamamoto;Gaku Yamamoto;Gaku YAMAMOTO;Chiharu AGAWA;R.Sasaki
通讯作者：
R.Sasaki

Pyrene-sensitized electron transport across vesicle bilayers : dependence of transport efficiency pyrene substituents

跨囊泡双层的芘敏化电子传输：传输效率的依赖性芘取代基