Proximity-Induced H-Aggregation of Cyanine Dyes on DNA-Duplexes

Nicoli, Francesca; Roos, Matthias K.; Hemmig, Elisa A.; Di Antonio, Marco; Vivie-Riedle, Regina de und Liedl, Tim (2016): Proximity-Induced H-Aggregation of Cyanine Dyes on DNA-Duplexes. In: Journal of Physical Chemistry A, Bd. 120, Nr. 50: S. 9941-9947

Abstract

A wide variety of organic dyes form, under certain conditions, clusters know as J- and H-aggregates. Cyanine dyes are such a class of molecules where the spatial proximity of several dyes leads to overlapping electron orbitals and thus to the creation of a new energy landscape compared to, that of the individual units. In this work, We create artificial H-aggregates of exactly two Cyanine 3 (Cy3) dyes by covalently linking them to a DNA molecule with controlled subnanometer distances. The absorption spectra of these coupled systems exhibit a blue-shifted peak, whose intensity varies depending on the distance between the dyes and the rigidity of the DNA template. Simulated vibrational resolved spectra, based on molecular orbital theory, excellently reproduce the experimentally observed features. Circular dichroism spectroscopy additionally reveals distinct signals, which indicates a chiral arrangement of the dye molecules. Molecular dynamic simulations of a Cy3-Cy3 construct including a 14-base pair DNA sequence verified chiral stacking of the dye molecules.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik ; Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik ; 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 1089-5639
• Sprache: Englisch