Nano Energy Research

Fluorescent Diaminoterephthalates – New Tools for Life Sciences and Materials Science

Principal Investigator: Prof. Dr. Jens Christoffers
Collaboration: Prof. Dr. Karl-Wilhelm Koch, Prof. Dr. Thorsten Klüner, Prof. Dr. Christoph Lienau, Prof. Dr. Walter Neu

Diaminoterephthalates are colored compounds with pronounced fluorescence properties. Furthermore, they define a molecular scaffold which allow for the ligation of four effector groups for different applications in Biochemistry, Physics and Physical Chemistry. Of particular significance are "turn-on" fluorescence probes, which were developed recently in our group. An example is given in the Scheme below: The reaction of a non-colored diaminoterephthalate (in "turn-off" state) with thiols yields a product, which emits orange light ("turn-on" state, λem = 560 nm, quantum yield 80%). In close cooperation with biochemists we have used these tools for investigating conformational changes of neuronal proteins in dependence of Ca2+-concentrations with FRET-experiments.

We are moreover designing model compounds for solar cells in close cooperation with physicists: Equipped with an electron donor and an electron acceptor, the dyes are investigated by femtosecond spectroscopy to gain insight into mechanistic details of photoinduced charge separation processes. Furthermore, the fluorescence-scaffolds are functionalized with thiol or silane groups for binding to gold or glass surfaces. Together with an alkyne or azide moiety present at the scaffold, biomolecules could be immobilized at the surface. In certain cases, this conjugation could be the "turn-on" or "turn-off" process for fluorescence.