Two-Dimensional DNA-Mimetic Molecular Organizations at the Air−Water Interface

• Published in: Journal of the American Chemical Society Vol. 119; no. 9; pp. 2341 - 2342
• Main Authors: Shimomura, Masatsugu, Nakamura, Fumio, Ijiro, Kuniharu, Taketsuna, Hirotaka, Tanaka, Masaru, Nakamura, Hiroshi, Hasebe, Kiyosi
• Format: Journal Article
• Language: English
• Published: American Chemical Society 05.03.1997
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja962847u

Tailoring of molecular organization is one of final goals of supramolecular chemistry and essential for designing molecular devices. Weak intermolecular interactions (e.g., hydrogen bonds, van der Waals forces, and hydrophobic interactions) are indispensable architectural tools for assembling molecular organizations. Double-helical DNA, one of natural products of molecular organization based on the specific intermolecular interaction, comprises one-dimensionally-stacked base pairs, adenine-thymine and guanine--cytosine, formed by complementary multiple hydrogen bonds. In addition to transferring molecular information as genetic signals, DNA has recently been discovered to transfer an electron through the stacked base pairs. Toward the functional application of the stacked base pairs as molecular devices, we report here the tailoring of two-dimensional DNA-mimetic molecular organizations with the specific intermolecular interaction at the air--water interface. A hydrophobic interface of a monolayer assembly formed on a water surface has been reported to be a sufficient environment for hydrogen bonding even though the chemical substances are surrounded by a large number of water molecules. Monolayer-forming amphiphilic nucleobases have already been prepared to demonstrate complementary hydrogen bonding with water-soluble bases at the air--water interface. Base pairing at the air--water interface might be a driving force of molecular organization termed "molecular-recognition-directed self-assembly." We are interested in how nucleobase amphiphiles are organized to two-dimensional (2-D) molecular assemblies by the complementary base-pairing at the base pair interface. In this paper, we have used microscopic fluorescence imaging of the base pair interface for the morphological observation of 2-D molecular assemblies.