Real-time breath analysis with IONICON PTR-MS is a promising field of research with numerous applications. The BET breath sampler is a special inlet system for breath gas analysis that can be connected to your PTR-MS instrument. It has been developed for optimal transfer of breath into an analyzer.
The test subject exhales through a tube and the PTR-MS draws a constant flow of sample gas through a connected capillary (see figure). The IONICON Buffered End-Tidal (BET) breath sampler has many advantages to facilitate and optimize real-time breath gas analysis. The BET sampler is compliant with medical device directives and is certified for clinical breath analysis with any of IONICONs PTR-MS instruments.
Advantages of Buffered End-Tidal Breath Sampling
Our patented Buffered End-Tidal sampling setup has many advantages for real-time breath analysis. The test subject applies one exhalation through the buffer tube and then recedes from the sampler to continue normal breathing. The end-tidal part of the breath remains buffered in the tube and is slowly drawn into the instrument. With a buffer volume of about 30 ml, the time to analyze the end-tidal breath can be extended 10-20 fold to several seconds. Without this buffering the time to analyze the end-tidal fraction is only a few hundred milliseconds. This increase is especially important for quadrupol based PTR-MS instruments, since it allows analyzing more compounds from a single exhalation, but is also advantageous for PTR-TOFMS instruments: With this extended integration time, it is possible to analyze all compounds in a TOF spectrum down to single digit pptv-levels – from a single exhalation.
With BET sampling, the subject can breathe normally throughout most of the measurement. This is a more comfortable and for the subject and prevents hyperventilation. Moreover, the patients subjects do not have to inhale through the setup.
Non re-breathing mouthpieces
The test subjects come only into contact with the detachable mouthpiece. These are commercially available, cheap and disposable. They have a saliva trap to avoid droplets entering the buffer tube and feature a non-rebreathing mechanism. This is in-line with the BET sampling principle and renders an additional bacterial filter unnecessary, avoiding loss of compounds.
The outside of the BET sampler can be disinfected. All surfaces in contact with the sample gas are of highly inert material, which is essential for trace gas analysis. The inner surfaces are uniformly heated to 70 °C to avoid condensation of humid breath and adsorption of compounds. An insulation layer ensures that the temperature on the outside is only slightly elevated.
Easy to use – quick connect system
The buffer tube is a PTFE tube and can quickly be replaced. The new quick-connect system facilitates the connection of the sampling capillary: At the top of the capillary, a SilcoNert2000® treated metal needle is attached. By plugging the BET inlet hose to the buffer tube part, the needle pierces a hole through the new PTFE tubing, providing a tight connection and a proper fit.
Clinical compliance – ISO/IEC 60601
IONICON has developed the BET-med system to comply with the standards for medical devices (ISO 60601). In May 2013 the clinical phase has been successfully completed and the BET-med system has been approved for clinical use by a notified body, TÜV Austria. It consists of a BET sampler and a heating controller unit, which is electrically separated from the laboratory device, the IONICON PTR-MS. The BET inlet hose is 2 m long to place the analyzer outside the so-called patient area. This allows real-time breath analysis in a clinical setting with all of IONICON’s PTR-QMS and PTR-TOFMS series instruments.