Entering a New Dimension in On-line Mass Spectrometry

SRI stands for Switchable Reagent Ions and describes a new feature where instead of the single precursor ion (H3O+ ) used so far in PTRMS systems also NO+ and O2 + can be used to chemically ionize trace

constituents in gas samples.

The benefits are extraordinary as not only isomeric VOC compounds can be separated and instantaneously quantified (the separation of isobaric compounds is already possible by using the IONICON HRS PTR-TOF-MS) but also substances with a smaller proton affinity (PA) than the PA of H2O can now be detected with help of SRI techniques.

Unlike many other technologies the Ionicon (Austria) PTR+SRI-MS instruments provide ultra-low detection limits in the single-digit pptvrange (reaching now even the ppqv detection regime) and very high sensitivity.

PTR+SRI-MS technology is now available with most IONICON products as an option or as upgrade for your existing PTR-MS instrument.