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Supramolecular nanopatterns self-assembled by adenine-thymine quartets at the liquid/solid interface.

Wael Mamdouh·Mingdong Dong·Sailong Xu·Eva Rauls·Flemming Besenbacher
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Abstract

By means of scanning tunneling microscopy (STM), we have observed for the first time well-ordered supramolecular nanopatterns formed by mixing two complementary DNA bases: adenine (A) and thymine (T), respectively, at the liquid/solid interface. By mixing A and T at a specific mixing molar ratio, cyclic structures that were distinctly different from the structures observed by the individual base molecules separately were formed. From an interplay between the STM findings and self-consistent charge density-functional based tight-binding (SCC-DFTB) calculation method, we suggest formation of A-T-A-T quartets constructed on the basis of A-T base pairing. The formation of the A-T-A-T quartets opens new avenues to use DNA base pairing as a way to form nanoscale surface architecture and biocompatible patterned surfaces particularly via host-guest complexation that might be suitable for drug design, where the target can be trapped inside the cavities of the molecular containers.

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1-OctanolAdenineGraphiteMicroscopy, Scanning TunnelingModels, MolecularNanostructuresThymineJournal ArticleResearch Support, Non-U.S. Gov't

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Wael Mamdouh, Mingdong Dong, Sailong Xu, Eva Rauls, Flemming Besenbacher. 2006-10-11. Supramolecular nanopatterns self-assembled by adenine-thymine quartets at the liquid/solid interface.. https://doi.org/10.1021/ja064988u

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