Continuous wave terahertz spectroscopy system designed for medical field

Abstract

We have constructed a continuous wave (CW) terahertz spectroscopy system using photonic integration-compatible technology. This system is intended for use in the medical field as a miniaturized terahertz spectroscopy system, in contrast to the conventional pulsed wave method. This system can simultaneously measure the absorption and phase (dielectric constant) responses of a sample, and it exhibits a dynamic range of at least 75 dB at under 1 THz. In addition, we used the CW spectroscopy system to identify a new type of complex molecule crystal (cocrystal) formed from a molecule of a pharmaceutical drug and various coformers. Cocrystals have been developed for use in the pharmaceutical manufacturing field to improve the solubility and absorbability of medicines. By fixing the measurement frequency at the absorption peak of intermolecular interactions of those crystals, we obtained a two-dimensional distribution of cocrystals within a test tablet.