PTR-MS 移動式/固定式 質子轉化反應質譜儀
1. PTR-MS (Proton Transfer Reaction – Mass Spectrometry) enables simultaneous real-time detection,monitoring and quantifi cation of volatile organic compounds (VOCs) such as acetone,acetaldehyde, methanol, ethanol, benzene, toluene, xylene and many others present in ambient air. Originally developed by scientists at the Institut für Ionenphysik at the University of Innsbruck, this technology has been commercialized by IONICON Analytik in 1998. Since then the IONICON PTR-MS instruments have been known for their outstanding sensitivities and market-leading detection limits in the single-digit pptv-levels and below.

2. Online quantification without calibration.

PTR-MS provides absolute quantitative analysis in real-time. The generation of the precursor reagent ions and the chemical ionization of the VOCs are individually controlled and spatially separated processes. This leads to constant and well defined conditions in the drift tube (unlike IMS, APCI-MS and similar technologies) making the determination of absolute concentrations possible without the use of gas standards.

 

3. Market-leading low online detection limit.

H3O+ ions do not react with any of the major components present in clean air due to their low proton affinity. Unlike other technologies (e.g. SIFT-MS or IMR-MS) PTR-MS does not dilute low concentrated samples by a carrier gas and does not lose precursor ions on their way through a mass filter between the ion source and the drift tube. This makes PTR-MS very sensitive to trace gases in the sample air. Very high intensities of precursor ions and thus real single-digit pptv-range detection limits for both, quadrupole and time of flight based instruments, are the resulting benefits of our PTR-MS technology.

4. Soft and efficient chemical ionization

Proton transfer from H3O+is a soft ionization method, keeping fragmentation rates rather low as compared to e.g. electron impact ionization often used in GC-MS instruments, thus minimizing coincidences in the mass spectra and improving the identification capability.

5. No sample preparation

A major advantage of PTR-MS is that the samples do not need to be prepared before the measurement (e.g. pre-concentration or chemical separation procedures), thus whole-air samples can be introduced directly into the drift tube allowing for dynamic headspace sampling or VOC flux measurements.

6. The real-time advantage

PTR-MS is an "online" mass spectrometric technology providing real-time data due to its very fast response time of less than 100ms, allowing e.g. for BVOC flux measurements. Averaging over minutes and long sampling intervals as in the case of less sensitive or "offline" technologies are not necessary with an IONICON PTR-MS.

7. The liberty to choose between quadrupole and time of flight MS

IONICON offers a broad range of different PTR-MS products and gives you the choice between different quadrupole mass filters or a time of flight analyzer for maximum flexibility and adaptation to your needs. Time of flight based trace gas analyzers as compared to mass filter based technologies (e.g. SIFT-MS or IMR-MS) have many advantages such as better separation and identification capabilities due to higher resolution and acquisition of the entire mass range in split-seconds which increases speed and sensitivity especially for complex mixtures.

8. Robust and easy to use

No gas supply is necessary to operate an IONICON PTR-MS (i.e. for H3O+ and NO+ reagent ions). Our instruments are light-weight (e.g. the portable PTR-QMS 300 weights only 70 kg) and space-saving which clearly puts us ahead of competing technologies. IONICON PTR-MS systems are often used for field campaigns or variable location measurements and can be operated in nearly every environment. Only 15 minutes after pressing the power-button, the PTR-QMS 300 is ready to measure. Little maintenance and small operating costs complete the whole package.