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Updated: Jan 23, 2026

Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor
Published on: August 30, 2012
Analysis of Human Breath by Millimeter-Wave/Terahertz Spectroscopy
Nick Rothbart1,2, Olaf Holz3,4, Rembert Koczulla5,6,7,8
1Institute of Optical Sensor Systems, German Aerospace Center (DLR), 12489 Berlin, Germany. nick.rothbart@dlr.de.
Abstract:
Breath gas analysis is a promising tool for medical research and diagnosis. A particularly powerful technological approach is millimeter-wave/terahertz (mmW/THz) spectroscopy, because it is a very sensitive and highly selective technique. In addition, it offers the potential for compact and affordable sensing systems for wide use. In this work, we demonstrate the capability of a mmW/THz spectrometer for breath analysis. Samples from three volunteers and a sample from ambient air were analyzed with respect to 31 different molecular species. High-resolution absorption spectra were measured by scanning two absorption lines from each species. Out of the 31, a total of 21 species were detected. The results demonstrate the potential of mmW/THz spectroscopy for breath analysis.
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