Institut für Chemie neuer Materialien

Navigation und Suche der Universität Osnabrück



Dr. Ana Maria Lepadatu


Subject of Ph.D.-Thesis:

Synthesis and characterization of redox dendrimers with recognition function on the periphery for well-defined supramolecular structures. „Kit molecules with variable periphery“

The objective of the project is to synthesize novel “patterned” polycationic structures, with a redox-active matrix consisting of 4,4’-bipyridine units and a biologically active label , e.g. an N-heterocycle (purines like Guanine or Adenine, pyrimidine bases like Thymine or Cytosine or derivatives as Chlorpyrrolo[2,3-d]pyrimidin) a kind of “recognition functions” for biological substrates – and to analyze the properties and the interaction between such substrate and biologic target.
The idea for the synthesis is to create a well-defined supramolecular structure with of a several hundred nanometers self-assembled by oligonucleotides ( dN20 ) and nucleobase-appended 4,4’-bipyridinium core thought complementary hydrogen bound formation and the Pi-Pi stacking interaction to form synthetic electron or ion channel. We expect specifically high sensitivities by the electro-active parts of the molecules when docked to a linking partner, whichexhibit enhanced optical and electronic properties due to intra- or interchromophonic interaction (charge transfer complexation) and produce a detectable electrochemical responses.

Redox - Dendrimer ssDNA supramolecular structures

Redox - Dendrimer ssDNA supramolecular structures

The configuration and structure of the novel supramolecular aggregates will presumably vary according to the nature of molecules on the periphery. The properties and the consistency of the structure of such aggregates – especially with regard to their stability and the charge transport – are to be analyzed by means of diverse methods in terms of pH-value, concentration, temperature and counter ions.