THz spectroscopic characterization of biomolecule/water systems by compact sensor chips

We demonstrate the terahertz (THz) spectroscopic performance of highly integrated sensor chips based on microstrip lines by measuring biomolecule/water systems. The concentration resolution of the present chips reaches down to 0.05 g/ml. We have confirmed that the number of bound water molecules per biomolecule can be obtained with precision using solid state transmission lines. The chips are highly suitable for the inspection of small amounts of specimen and for the application to a wide range of water rich materials. Our method may therefore be a good candidate for a simple liquid sensor working in the THz regime