New method to investigate the chemistry of nanoparticles developed

The researchers at Tampere University and Finnish Meteorological Institute developed a new method to investigate the chemical composition of nanoparticles (less than 50 nanometers in diameter). In the method, the studied nanoparticles are attached on the surfaces of artificially generated soot particles, which enables their detection with the soot particle aerosol mass spectrometer. Normally, nanoparticles would be lost in the aerodynamic lens of the instrument. This new soot particle generation and agglomeration process is called Soot Particle Agglomeration Inlet (SPAI).

The prototype of SPAI was tested in the laboratory with silver nanoparticles. Applying the SPAI resulted in a 35-fold enhancement in the silver nanoparticle detection compared to the measurement without it. In addition to silver particles, SPAI can be utilized for the other chemical species that are not included in the generated soot aerosol, e.g. metals. In the future, SPAI will be applicable specially in the field of engine exhaust emissions since the knowledge on the chemical composition of exhaust nanoparticles is insufficient.

More information:

Senior scientist Sanna Saarikoski, Finnish Meteorological Institute, sanna.saarikoski@fmi.fi

Senior scientist Hilkka Timonen, Finnish Meteorological Institute, hilkka.timonen@fmi.fi

Martikainen, S., Saarikoski, S., Juuti, P., Timonen, H., Keskinen, J., Karjalainen, P. (2021). Soot Particle Agglomeration Inlet (SPAI) for Enabling Online Chemical Composition Measurement of Nanoparticles with the Aerosol Mass Spectrometer. Aerosol Air Qual. Res. Read the scientific article here: https://doi.org/10.4209/aaqr.200638