Proteins are crucial to almost every biological process. The great diversity and versatility of proteins make them important, e.g., in the catalysis of chemical reactions, in the transport and storage mechanisms and in the immune reaction of the human body. However, proteins can also be a threat to our body and play an important role in the origination of diseases as the Alzheimer's disease.
With dielectric spectroscopy, proteins can be examined not only in the solid state (i.e. as powder), but also under nearly in vivo conditions (solved in water). This is important, because water is essential for the biological functions of proteins and hence the investigation of the interaction of water with proteins is a very active field of research. At our laboratories we are capable of determining the dielectric properties of a sample over a very broad frequency range (10-6-1015) by combining different measurement techniques and devices. Therefore we are able to investigate many different aspects of protein dynamic as, for example, relaxation processes (see the schematic figure) and the "glass transition".
We also intend to shed light on the water-protein interaction to evaluate the role of water for the protein dynamics and functionality.



Schematic view of the typical loss spectrum of a protein solution. The β- and γ-relaxations arise from the tumbling motions of the protein and the water molecules, respectively. The origin of the δ-relaxation is still controversially discussed.  


For further details, see:

  1. Relaxation dynamics of a protein solution investigated by dielectric spectroscopy
    M. Wolf, R. Gulich, P. Lunkenheimer, and A. Loidl
    Biochim. Biophys. Acta. 1824, 723 (2012).
  2. Dynamics of protein hydration water
    M. Wolf, S. Emmert, R. Gulich, P. Lunkenheimer, and A. Loidl
    Phys. Rev. E 92, 032727 (2015).