The principle of the Metrohm AeRosol Sampler, or "MARS" for short, is simple: air flows continuously through the so-called Wet Rotating Denuder into the instrument to remove interfering gases. Freed from its gaseous, water-soluble components, the air enters a vapor jet aerosol collector. There, supersaturated steam is introduced, causing the aerosols to grow into larger, heavier droplets, which are then separated into water by inertial separation and can be sampled for further analysis.
The AeRosol Sampler MARS is suitable for preparing samples for monitoring of indoor or outdoor air. For the analysis of anions and cations in aerosols, an ion chromatograph (IC) can be connected directly to the instrument. When monitoring particles in ambient air with MARS-IC, an internal standard can be added. This internal standard contains a known amount of lithium and bromide, which ensures continuous validation of the results.