Breath test equipment

Determination of 13С/12С isotope ratio in exhaled carbon dioxide can be made by different analyzers, first of all, by equipment which is specially designed for breath test applications.

The mostly widespread analysers are specialized mass-spectrometers which conditioned by their serviceability. Mass-spectrometers are expensive devices ($60 000-150 000) but call for infrequent technical support and have the highest precision of measurements. They are able to determine 13С/12С isotope ratio with the accuracy 0,1-0,3 ‰.

Specialized mass-spectrometers are producted by MediChem ( Korea, Heliview), Finnigan (BreathMat), at al.

The example of mass-spectrometers destined for common purposes but also used in breath test is IsoРrime from Microsomass company. TraceGas module attached to mass-spectrometer is equiped by chemical traps for H2O, СО2 и NO2 separation. As a rule the sample analysis by means of any above-listed mass-spectrometers takes 2 min; volume of sample investigated is 15-100 ml, all mass-spectrometers are handled by a computer and ensure automated data transfer and processing. 13С/12С isotope ratio in breath can also be measures by alternative analysers based on opto-galvanic effect (LARA), absorption IR-spectroscopy and opto-acoustic registration methods (IRIS), etc. The listed analysers precision is 0.5 ‰, the sample volume is about 500 ml, and СО2 concentration in breath should be no less than 2%. The certain advantage of alternative analyzers is their price category - $ 30 000-60 000.