Developing of On-Line CO2 Isotopologues Detecting Method on the Base of Semiconductor Laser Near 4873 cm-1 in Gaseous Media

Development of laser noninvasive on-line diagnostics of oncological diseases based on the absorption method in the 4860–4880 cm−1spectral range

“…Our previous work suggested that diode laser spectr oscopy and absorption methods can be advantageous for highly sensitive and selective on-line analysis of various molecular compounds in gaseous and liquid media [12][13][14]. Here, we report the development of an optical measuring system for selective analysis of gaseous mixtures containing 12 СО 2 and 13 СО 2 .…”

“…Simple and noninvasive methods are preferred for prevention and early diagnostics of diseases for enabling timely therapeutic intervention. Some state-of-the-art methods utilize the air expired by patients, measuring the content of 12 С and 13 С isotopes in expired 12 СО 2 and 13 СО 2 , respectively, which are released after splitting labeled urea by H. pylori urease [8]. It must be noted that the accuracy required by these breath tests is in the 3%-5% range [9,10].…”

“…Among the methods for measuring concentrations of C isotopes in the expired air, those based on absorption spectr oscopy are the most promising, combining high sensitivity and accuracy with the ability to obtain results in real time [11][12][13][14][15]. In these methods, frequency-tunable diode lasers (TDLs) operating in the infrared spectral range near the wavelengths of 4.3, 2 and 1.6 μm are used as radiation sources.…”

“…First, compared with 4.3 μm wavelength lasers, 2 μm wavelength lasers are easier to maintain because they do not require cryogenic cooling. Second, this spectral range contains the 12 СО 2 and 13 СО 2 absorption bands with peak absorption intensities exceeding those of 1.6 μm wavelength lasers by two orders of magnitude, providing higher sensitivity for detecting 12,13 СО 2 isotopologues in gaseous mixtures.…”

Methods of14СО2,13СО2and12СО2detection in gaseous media in real time

“…Developing methods and techniques of high-sensitivity selective detection of carbon isotope content in gaseous media of various compositions in real time is an important practical task in the nuclear power industry, medicine, geophysics and other fields of knowledge [1][2][3][4][5][6][7]. The task of detecting 14 С and 13 С isotopes has particular importance.…”