Dielectric Response of Suspended Nucleotides at Terahertz Frequencies

Terahertz time domain spectroscopy (THz-TDS) was used to determine the dielectric response of hydrated nucleotides at different concentrations. A Debye model with two relaxation times was used to fit the data for each concentration. We found that the hydrogen-network structure of the hydrated purine nucleotides is more stable than that of the pyrimadines. A suspension model was used to separate the dielectric response of the hydrated nucleotide from that of bulk water, and from this analysis the thickness of the hydration layer is determined.