Terahertz spectroscopy of short-chain polypeptides

Freeform Fabrication of Magnetophotonic Crystals with Diamond Lattices of Oxide and Metallic Glasses for Terahertz Wave Control by Micro Patterning Stereolithography and Low Temperature Sintering

“…The device component of 5.0 × 5.0 × 0.5 mm in external dimensions was formed through connecting unit cells of 10 × 10 × 1 in numbers. The transition temperature for the crystal phase of the selected metallic glass with the amorphous structure was measured as 552 °C in the previous research [7][8][9]. The melting temperature of the selected oxide glass was 450 °C approximately.…”

“…The spectroscopic technologies are expected to be applied to sensors for real time detecting toxic materials [6,7]. However, the terahertz waves are difficult to transmit into the water solvents due to electromagnetic absorptions [8]. Novel resonators to concentrate the electromagnetic wave energies are required strongly.…”

Fabrication of Photonic Crystal Cavities for Terahertz Wave Resonations

“…Moreover, the terahertz sensing technologies for aqueous phase environments in nature fields to detecting dissolved matters directly are extremely interesting topics. However, the terahertz waves are difficult to transmit into the water solvents with millimeter order thickness corresponding to the several wavelengths due to electromagnetic absorptions (Kutteruf;.…”

Analytical Terahertz Spectroscopy

“…23 Since the THz frequency matches the low-frequency vibration and the vibration modes of weak interactions, such as hydrogen bonds, THz-TDS constitutes a unique tool for studying various molecules and materials whose molecular and/or crystal structures are stabilized by these weak interactions. The steric structures of many biological molecules are stabilized by hydrogen bonds, and THz-TDS studies have been undertaken on proteins, 26 polypeptides, 7,27,28 and DNA. 29,30 Figure 3(a) shows the absorption spectra of myoglobin powder obtained with THz (solid line) and Fourier-transform infrared spectroscopy (dotted line).…”

“…As the chain length increases, distinct and new absorption features were produced. 27 Because a protein molecule consists of a long polypeptide chain, it is reasonable that the number of normal modes increases beyond the spectral resolution. It is worth mentioning that aqueous samples of these molecules are difficult to observe with transmission THz-TDS owing to the high absorption of THz waves by polar liquids, such as water.…”