Enter the new dimension of online mass spectrometry with IONICON PTR+SRI-MS featuring H₃O⁺, NO⁺ and O₂⁺ as precursor ions.

Quantify more volatile compounds than ever in real-time with PTR+SRI-MS and take advantage of single-digit pptv-level detection limits, only available with IONICON PTR-MS.

Order your new IONICON PTR-MS with SRI (switchable reagent ions) capabilities or consult with us concerning upgrade capabilities of your instrument.

Advantages of using H₃O⁺, NO⁺ and O₂⁺ as precursor ions

H₃O⁺ is ideal for many applications as our customers have proven for more than a decade. In some cases however it can be useful to use more than one reagent ion in your PTR-MS.

By using PTR+SRI-MS isomeric VOC compounds can be separated and instantaneously quantified (the differentiation of isobaric compounds is already possible by using IONICON PTR-TOF-MS).

NO⁺ is like H₃O⁺ a soft ionizer, ionization occurs mainly through charge transfer, whereas O₂⁺ is found to be a less soft chemical ionization agent and can be used where proton transfer from H₃O⁺ does not work. Therefore more VOCs than ever can be quantified in real-time with PTR+SRI-MS.

Market-leading detection limit also with PTR+SRI-MS

We have developed a PTR+SRI-MS where the chemical reagent ions NO⁺ and O₂⁺ are generated in our ion source at intensities matching or in case of NO⁺ even surpassing those of traditional IONICON PTR-MS H₃O⁺ ions by up to 40%, thus enabling ultra-high sensitivity and ultra-low detection limits also for this new dimension of PTR-MS technology.

This overcomes one of the biggest down-sides of competing technologies like SIFT-MS, where mass pre-selection of ions is employed and a carrier gas dilutes the sample, at the expense of some two orders of magnitude lower detection sensitivity for VOCs.

The PTR+SRI-MS products

H₃O⁺,NO⁺ and O₂⁺ as precursor ion package is available as an option for the following IONICON products: