J. Phys. IV France 125 (2005) 773-775
Isotope-selective sensor for medical diagnostics based on PASM. Wolff1, 2, H.G. Groninga1 and H. Harde2
1 PAS-Tech GmbH, Bahnhofstrasse 3, 19246 Zarrentin, Germany
2 Helmut-Schmidt-University, Holstenhofweg 85, 22043 Hamburg, Germany
Development of new optical sensor technologies has a major impact on the progression of diagnostic methods. Of the permanently increasing number of non-invasive 13C-breath tests, the Urea Breath Test for detection of Helicobacter pylori is the most prominent. However, many recent developments go beyond gastroenterological applications. We present a new detection scheme for breath analysis that employs an especially compact and simple set-up based on Photoacoustic Spectroscopy. Using a wavelength-modulated DFB-diode laser and taking advantage of acoustical resonances of the sample cell, we performed very sensitive isotope-selective measurements on CO2. Detection limits for 13CO2 of a few ppm and for the variation of the 13CO2 concentration of approximately 1% were achieved.
© EDP Sciences 2005