Environmental research

PTR-MS ultra sensitive online monitoring of air pollutants

PTR-MS systems of Ionicon are used intensively in environmental research. Applications in nature need a very low detection limit in combination with the fast response time being the main advantages of our technology.
Different researchers and institutions all over the planet contribute to the better understanding of the world we live in. We help them to achieve their scientific goals.

Atmospheric chemists analyze VOCs in the troposphere with our equipment and are able to quantify substances which are in the air we breathe in concentrations as low as 1 pptv in real-time without the need for sample preparation.

Monitoring of roadside air VOCs in high resolution

click to enlarge The IONICON PTR-TOFMS series features not only a very low detection limit for most common VOCs but delivers results with a very high mass resolution and quantification of the whole unlimited mass range in one scan. This allows our customers to discriminate isobars and get substantially more information from the data collected.

The graph on the left side shows a very good example of very low concentrated isobars that were detected using the PTR-TOF 8000 instrument. The substances have the same nominal mass and cannot be distinguished using a quadrupole. Using a time of flight however we were able to identify them as C3H6O2 likely acetic acid methyl ester and formic acid ethyl ester at 75.0446 and C4H10O likely dimethylethanol at 75.081.

VOCs in the troposphere - single-digit pptv level quantification with PTR-MS

click to enlarge Road traffic contamination is quantifiable even in over 3000 meters altitude. This has been successfully demonstrated in early PTR-MS studies.

Tropospheric VOCs at higher altitudes have been measured in in long-term investigations at the top of the Sonnblick, Austria (3100m altitude) and in flight experiments up to 12km elevation above the rain forest in South America. Meteorologists have calculated back-trajectories and thus more information on the measured VOCs could be gathered. Moreover the PTR-MS analysis were validated.

PTR-MS ambient air VOC monitoring on flight campaigns

IONICON has a lot of experience in creating customized solutions for special tasks. Several instruments have already been built-in into planes and other vehicles.

A IONICON PTR-MS has been used at a project called "Aircraft Measurements of Highly Reactive Volatile Organic Compounds Using Proton Transfer Reaction Mass Spectrometry (PTR-MS) During TexAQS II".

It shows that our systems can monitor VOCs online, in a very high time resolution and nevertheless with a very low detection limit.

Download the final report!

PTR-MS on-road VOC monitoring of vehicle exhaust

Our instruments are perfectly well suited for field campaigns as a lot of scientists have successfully proven over the last decade. One of them is Prof. Berk Knighton, Montana State University, who installed an IONICON PTR-MS in a mobile lab to monitor engine exhaust in real-time, "chasing" single vehicles in Mexico City Metropolitan Area's traffic.

It was shown that the results differ according to vehicle condition, fuel quality and driving behavior. Experience this experiment in an illustrative video sequence (15 mb, quicktime, courtesy of Prof. Knighton).

Description of video content:
You will see a picture of the vehicle being monitored in the upper left hand. On the bottom you will see the evolution of two signals: (1) CO₂, a combustion tracer to verify that the mobile lab is intercepting the vehicles exhaust plume; and (2) PTR-MS signal at m/z 57, an ion fragment formed from the detection of MTBE, a fuel additive in Mexican fuel. In the upper right hand panel you will see a correlation scatter plot of the m/z 57 signal expressed as ppbv versus the CO₂ concentration. The slope represents the emission ratio.