Characterization of microplastics using fluorescence spectroscopy and online single particle fluorescence measurements

Microplastic particles in the atmosphere, even in very remote locations (Allen 2021; Allen 2019, Materić 2020, 2021), have attracted considerable interest in recent years. The origin, chemical transformation, transport and abundance of airborne microplastics still remains largely unexplained. Detection techniques are scarce and often include visual classification with the naked eye or with an optical microscope (Lulu 2021).

In this study, fluorescence spectroscopy is used to characterize microplastic particles in the laboratory. Pure samples of polyethylene terephthalate (PET), polyethylene (PE) and polypropylene (PP), as well as everyday products (PET-drinking bottle, packaging) were shredded with a swing mill into particles < 100 μm. The samples were analyzed with a fluorescence spectrometer, revealing clear excitation-emission maxima, with slight differences among the samples. To test if fluorescence is a promising property for the online detection of airborne microplastics, we use a Bioaerosol Sensor, which enables single particle fluorescence measurements at two excitation wavelengths and in two emission windows. For this aim, the microplastic particles are dispersed in air and are characterized by the bioaerosol sensor.

 

Literature:

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Allen, Steve, et al. "Atmospheric transport and deposition of microplastics in a remote mountain catchment." Nature Geoscience 12.5 (2019): 339-344.

Materić, Dušan, et al. "Nanoplastics transport to the remote, high-altitude Alps." Environmental Pollution 288 (2021): 117697.

Materić, Dušan, et al. "Micro-and nanoplastics in Alpine Snow: a new method for chemical identification and (semi) quantification in the nanogram range." Environmental science & technology 54.4 (2020): 2353-2359.

Lv, Lulu, et al. "Challenge for the detection of microplastics in the environment." Water Environment Research 93.1 (2021): 5-15.