nucleic acids; fluorescence; aromatic stacking; self-organization; aromatic hydrocarbons; molecular beacon; supramolecular chemistry; charge transfer
S. Li, S.M. Langenegger, R. Häner (2013), Control of aggregation-induced emission by DNA hybridization, in Chem. Commun.
, 49, 5835-5837.
L.I. Markova, V.L. Malinovskii, L.D. Patsenker, R. Häner (2013), J- vs. H-type assembly: pentamethine cyanine (Cy5) as near-IR chiroptical reporter, in Chem. Commun.
, 49, 5298-5300.
F. Simona, A.L. Nussbaumer, R. Häner, M. Cascella (2013), Supramolecular Organization of Heptapyrenotide Oligomers - an in Depth Investigation by Molecular Dynamics Simulations, in J. Phys. Chem. B
, 117, 2576-2585.
T. Koch, A. Peutzfeld, V.L. Malinovskii, S. Flury, R. Häner, A. Lussi (2013), Temporary Zinc Oxide-Eugenol Cement: Eugenol Quantity in Dentin and Bond Strength of Resin Composite, in Eur. J. Oral. Sci.
, 121, 363-369.
Garo F, Haner R (2012), 2,1,3-Benzothiadiazole-Modified DNA, in EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
, (14), 2801-2808.
Garo F, Haner R (2012), A DNA-Based Light-Harvesting Antenna, in ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
, 51(4), 916-919.
A.V. Rudnev V.L. Malinovskii A.L. Nussbaumer A. Mishchenko R. Häner T. Wandlowski (2012), Cooperative and Non-Cooperative Assembly of Oligopyrenotides Resolved by Atomic Force Microscopy, in Macromol.
, 2012(45), 5986-5992.
S.M. Biner, R. Häner (2012), DNA Triplex-Mediated Assembly of Polyaromatic Chromophores, in Chem&Biodivers
, 9(11), 2485-2493.
F. Garo, R. Häner (2012), Influence of a GC base pair on excitation energy transfer in DNA-assembled phenantherene p-stacks, in Bioconjug. Chem.
, 23, 2105-2113.
Malinovskii VL, Nussbaumer AL, Haner R (2012), Oligopyrenotides: Chiral Nanoscale Templates for Chromophore Assembly, in ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
, 51(20), 4905-4908.
Adeyemi OO, Malinovskii VL, Biner SM, Calzaferri G, Haner R (2012), Photon harvesting by excimer-forming multichromophores, in CHEMICAL COMMUNICATIONS
, 48(77), 9589-9591.
Nussbaumer AL, Samain F, Malinovskii VL, Haner R (2012), Supramolecular polymerization of oligopyrenotides - stereochemical control by single, natural nucleotides, in ORGANIC & BIOMOLECULAR CHEMISTRY
, 10(25), 4891-4898.
L.I. Markowa, V.L. Malinovskii, L.D. Patsenker, R. Häner (2012), Synthesis and Properties of Squaraine-Modified DNA, in Org. Biomol. Chem.
, 10, 8944-8947.
Probst M, Wenger D, Biner SM, Haner R (2012), The DNA three-way junction as a mould for tripartite chromophore assembly, in ORGANIC & BIOMOLECULAR CHEMISTRY
, 10(4), 755-759.
Biner SM, Haner R (2011), A Two-Color, Self-Controlled Molecular Beacon, in CHEMBIOCHEM
, 12(18), 2733-2736.
Nussbaumer Alina L., Studer Daniel, Malinovskii Vladimir L., Häner Robert (2011), Amplification of Chirality by Supramolecular Polymerization of Pyrene Oligomers, in Angew. Chem. Int. Ed.
, 24, 5490-5494.
Wenger Daniel, Malinovskii Vladimir L., Häner Robert (2011), Modulation of Chiroptical Properties by DNA-guided Assembly of Fluorenes, in Chem. Commun.
, 47, 3168-3170.
Biner Sarah M., Kummer Dominic, Malinovskii Vladimir L., Häner Robert (2011), Signal Control by Self-Assembly of Fluorophores in a Molecular Beacon – A Model Study., in Org. Biomol. Chem.
, 9, 2628-2633.
M. Vybornyi, A.V. Rudnev, S.M. Langenegger, T. Wandlowski, G. Calzaferri, R. Häner, Formation of Two-Dimensional Supramolecular Polymers by Amphiphilic Pyrene Oligomers, in Angew. Chem. Int. Ed.
A. Devaux, G. Calzaferri, I. Miletto, P. Cao, P. Belser, D. Brühwiler, O. Khorev, R. Häner, A. Kunzmann, Self-Absorption and Luminescence Quantum Yields of Dye-Zeolite L Composites, in J. Phys. Chem. C
The construction and investigation of nucleic acid-guided, supramolecular structures is proposed. Building upon the results obtained in the past with pyrene and related polyaromatic compounds, we will use DNA-chromophore conjugates for the assembly of multi-stranded architectures. The synthesis and evaluation of novel types of non-nucleosidic chromophores will be pursued. At the same time, the spectroscopic and structural characterization of extended chromophore arrays is becoming a major aspect of our reserach.In a first part, we will explore new classes of aromatic building blocks. While we continue the investigation of additional types of pyrene derivatives we will extend our efforts to the synthesis of quinoxaline and porphyrin derivatives. The newly synthesized compounds will be evaluated for their stacking behaviour1,2 as well as their spectroscopic properties. Crucial aspects are the ability to assist hybrid formation, the fluorescence properties, and the compatibility with oligonucleotide synthesis. The proposed quinoxaline derivatives will provide an easy access to an extended library of compounds. Preliminary analysis of the spectroscopic properties of a first member of the series showed promising properties (high extinction coefficient and good quantum yield). The synthesis of the porphyrin derivatives as well as their incorporation into oligonucleotides is considerably more challenging. Considering the unique electronic properties of the porphyrins, the preparation of covalently linked stacks of defined length and composition is a worthy endeavour, however.3,4Secondly, we will extend our investigations of artificial helical systems formed by oligomers of pyrene and other building blocks. The amplification of chirality observed in a system composed of an achiral oligopyrene and traces of a (chiral) pyrene oligomer containing a single deoxynucleotide suggests that, under certain conditions, the oligomers form supramolecular polymers. The properties of these macromolecular assemblies will be further investigated with the different spectroscopic methods available. Along the same lines, we will explore the rational formation of molecular nanowires with bi-segmental oligomers composed of DNA and artificial building blocks (pyrene or PDI). Potential insight into the nature of these polymeric structures may be obtained through a collaborative effort with the group of T. Wandlowski of our department.Thirdly, the possibility of chemical ligation and template-assisted chain elongation of oligopyrenotides will be investigated. The formation of multi-stranded hybrids by oligopyrene strands via interstrand stacking interactions opens the opportunity of testing the formation of phosphodiester bonds from activated phosphate esters on (oligopyrene) template strands. Although not as efficient as enzymatic phosphodiester bond formation by enzymatic means and with natural substrates, such type of a templated oligomerization might provide a way to primitive, self-reproducing systems, especially if more than one type of building block were used.In a further part we will prepare modified hybrids that will allow the investigation of the efficiency of electron transfer through pi-stacks of non-nucleosidic, aromatic building blocks. For this purpose, oligomers containing pyrene (electron acceptor) and a quencher (electron donor) which are separated by a polyaromatic building block (e.g. phenanthrene) will be prepared. The determination of the relative fluorescence quantum yields will give information on the photo-induced electron transfer process.In addition to the above mentioned activities we will continue our efforts with the development of excimer based molecular beacons. In collaboration with the Department of Clinical Research (Prof. R. Jaggi), we will test differently designed beacon stems for their suitability for PCR and other applications.