Terahertz dielectric assay of solution phase protein binding

The authors demonstrate a method for rapid determination of protein-ligand binding on solution phase samples using terahertz dielectric spectroscopy. Measurements were performed using terahertz time domain spectroscopy on aqueous solutions below the liquid-solid transition for water. Small ligand binding sensitivity was demonstrated using triacetylglucosamine and hen egg white lysozyme with a decrease in dielectric response with binding. The magnitude of the change increases with frequency.