Design Aspects for Sensitive Metasurface-Based THz Biosensing in Aqueous Solutions

Metasurfaces can improve the sensitivity of THz biomolecule detection significantly. Still, the high absorptive properties of water-based matrices prevent direct measurements under physiologically relevant conditions. In this work, we present a collection of sensor designs focusing on their distinctive geometries and transmission behavior. One major advantage of the proposed structures is their preservation of a resonance feature in the frequency response, even for measurements in water. Consequentially, efficient THz detection of larger and more complex entities such as vesicular structures like exosomes becomes possible.