Lay summary
The aim of this project is to establish a center of competence for technetium chemistry focused on technetium (Tc) in higher oxidation states, to solve the emerging problems coming from the increasing production of the isotope 99Tc and to build a new strong future for technetium in medicine.

Techentium is the lightest chemical element with no stable isotope. The isotope 99Tc is a weak beta-emitter with a very long half life time of 2.13x10exp(5) years. It is formed as a byproduct in nuclear power plants and is a great problem for nuclear waste management, due to its high mobility. The meta stable nuclear isomer 99mTc is a gamma-emitter with a half life time of 6 h. These properties make it suitable for radiopharmaceutical applications and it is used today in over 80 % for standard radio diagnostics in medicine. Nevertheless, the number of young academics working on this important field is dramatically decreased in the last years. New impulses are needed to recall the importance of Tc chemistry and radiochemistry generally.

The combination of imaging with Tc and the so called nanomedicine, the application of nanotechnology to healthcare could have such an impact. The development of a stable, not air sensitive Tc system which can be specifically linked to a nanoparticle or bound irreversible to a macromolecule such as a polyoxometalate (discrete oxygen cluster anions of early transition-metals in their highest oxidation states) will create a new field of technetium chemistry with the potential to reactivate research efforts on this element in the future. To realize this idea collaboration between fundamental investigations with both isotops 99Tc and 99mTc, materials science and medicine is essential.

This research project will tackle scientific challenges from the most important fields for which technetium is essential and aims at putting the different topics on a common, molecular base. Namely, the chemistry of technetium oxygen complexes with technetium in higher oxidation states will be explored in its full range. Rather than developing for all fields different strategies and using different compounds, it is the incentive of this project to use the same molecular cores for applications which are apparently different but rely ultimately on the same chemical requirements, long term stability in water and well defined chemical environment. Last but not least, we expect to attract young students since, according to our experience, such interdisciplinary research problems are highly appreciated. Thus, the topics include a strong educational aspect which is urgently required due to a foreseeable lack of scientists with experience in radionuclide chemistry.