Excitation–Emission Fluorescence Mapping Analysis of Microplastics That Are Typically Pollutants

Micro- and nanoplastics (MNPs) pose a significant threat to marine and human life due to their immense toxicity. To protect these ecosystems, the development of reliable technologies for MNP detection, characterisation, and removal is vital. While FTIR and Raman spectroscopy are established methods for MNP analysis, fluorescence (FL) spectroscopy has recently emerged as a promising alternative. However, most prior research relies on FL emission probing with a single excitation wavelength for MNP detection. In this study, we introduce a two-dimensional (2D) fluorescence excitation–emission (FLE) mapping method for the detection of commonly found microplastics, namely polystyrene (PS), polyethylene terephthalate (PET), and polypropylene (PP). The FLE mapping technique enables the collective recording of emission spectra across a range of excitation wavelengths, revealing the dominant excitation–emission features of different microplastics. This research advances the field by offering a non-destructive and label-free identification of MNP contamination through the use of FL spectral fingerprints.