Characterization of Biological Molecules with Time-Domain Terahertz Spectroscopy

Terahertz (THz) spectroscopy is distinctly appealing for characterization of biological molecules because many biological compounds have vibrational modes within the THz range. These vibrational modes often lead to a unique spectrum for each substance, allowing easy differentiation. The aim of this study is to utilize time-domain terahertz spectroscopy to calculate the frequency-dependent absorption coefficient and refractive index for several amino acids and proteins, including bovine and human serum albumin, glycine, and L- and D-histidine. The histidine study seeks to investigate the optical isomer differention capabilities of THz spectroscopy. It is also hoped that the characterization of proteins will lead to further studies examining the conformational changes related to disease detection.