Raman Spectroscopy for Urea Breath Test.

The urea breath test is a non-invasive diagnostic method for Helicobacter pylori infections, which relies on the change in the proportion of 13 CO 2 in exhaled air. Nondispersive infrared sensors are commonly used for the urea breath test in laboratory equipment, but Raman spectroscopy demonstrated potential for more accurate measurements. The accuracy of the Helicobacter pylori detection via the urea breath test using 13 CO 2 as a biomarker is affected by measurement errors, including equipment error and δ 13 C measurement uncertainty. We present a Raman scattering-based gas analyzer capable of δ 13 C measurements in exhaled air. The technical details of the various measurement conditions have been discussed. Standard gas samples were measured. 12 CO 2 and 13 CO 2 calibration coefficients were determined. The Raman spectrum of the exhaled air was measured and the δ 13 C change (in the process of the urea breath test) was calculated. The total error measured was 6% and does not exceed the limit of 10% that was analytically calculated.