High-precision terahertz spectroscopy for noninvasive medicine diagnostics

Abstract In recent years methods for exhaled breath analysis have been developing all around the world. The exhaled breath analysis could result in a powerful tool for noninvasive medicine. The work presented in this paper is concerned with gas analyzers for exhaled breath diagnostics. The analyzers are based on high-precision spectrometers of the THz frequency range, which provide high resolution, high sensitivity and detect a wide range of detectable substances. The spectrometers work on non-stationary effects (phase-switching and fast sweep of frequency). The analyzers have been successfully applied for the detection of various biomarkers (nitric oxide, acetone, ammonia, methanol, ethanol) in the breath of conditionally healthy volunteers and patients with various cancerous and noncancerous diseases.