The THz dance of the protein with the water

We show that THz absorption measurements of solvated proteins is a new tool to probe the dynamical hydration shell around biomolecules. The measurement of the concentration dependent changes of the Terahertz absorption coefficient yields information on the solute induced changes of the solvation dynamics, its dependence on protein concentration, and the width of the dynamic hydration layer. The results show the potential of THz spectroscopy to yield answers on these biologically relevant questions.