Metrohm has revealed how combining its 850 Professional IC with a particle-into- liquid sampler allows real-time determination of anions and cations in aerosols.
Research on air pollution requires rapid and accurate measurements of inorganic species in ambient air.
Coupling a particle-into-liquid-sampler (PILS) to Metrohm's 850 Professional IC allows for quasi-continuous measurements with a temporal resolution of just five to 15 min.
The determination of anions and cations in atmospheric aerosols yields essential information concerning atmospheric transport and transformation processes.
Until now these determinations have been carried out using filters.
However, this method only allows one to determine averages over a time span of 24 hours or even more.
Moreover, the results can be compromised by desorption processes and chemical transformations.
In contrast to sampling devices relying on filters, using PILS allows semi-continuous sampling of aerosols downstream from a denuder system.
Subsequent to the removal of interfering gas-phase species, the remaining aerosol particles are dissolved into water phase by means of supersaturated steam.
Eventually, the liquid sample is transported to the IC for analysis.
The key benefit of this method is a high temporal resolution of measurements of five to 15 minutes.
Changes in the ionic composition of ambient air can therefore be recorded almost immediately allowing a more precise correlation with meteorological and other data.
