Abstract

Raman spectroscopy is gaining ground in the analysis of microplastics, especially due to its high spatial resolution that allows the investigation of small plastic particles, whose numeric abundance is argued to be particularly relevant in aquatic systems. Here, we aimed at outlining the status of Raman analysis of microplastics from aquatic systems, highlighting the advantages and the drawbacks of this technique and critically presenting tools and ways to effectively employ this instrument and to improve the spectra obtained and their interpretation. In particular, we summarized procedural information for the use of Raman spectroscopy, and we discussed issues linked to fluorescence interference and the analysis of weathered polymers, which may complicate the interpretation of Raman signatures. In this context, a deep understanding of the different plastic polymers and their Raman peaks and chemical fingerprints is fundamental to avoid misidentification. Therefore, we provided a catalog with detailed information about peaks of most common plastic polymers, and this represents, to the best of our knowledge, the first comprehensive resource that systematically synthesized plastic Raman peaks. Additionally, we focused on plastic additives, which are contained in the majority of plastics. These compounds are often intense in Raman scattering and may partly or completely overlie the actual material types, resulting in the identification of additives alone or misidentification issue. For these reasons, we also presented a new R package “RamanMP” that includes a database of 356 spectra (325 of which are additives). This will help to foster the use of this technique, which is becoming especially relevant in microplastic analysis.

© 2021 The Author(s)

Detection and analysis of microplastics in offshore sediment by microscopic differential Raman spectroscopy

Yang Dong, Qingsheng Xue, Fengqin Lu, Fupeng Wang, and Qian Li
Appl. Opt. 61(34) 10188-10196 (2022)

Design of a confocal micro-Raman spectroscopy system and research on microplastics detection

Jitao Lu, Qingsheng Xue, Haoxuan Bai, and Nan Wang
Appl. Opt. 60(27) 8375-8383 (2021)

Identification of microplastics in a large water volume by integrated holography and Raman spectroscopy

Tomoko Takahashi, Zonghua Liu, Thangavel Thevar, Nicholas Burns, Sumeet Mahajan, Dhugal Lindsay, John Watson, and Blair Thornton
Appl. Opt. 59(17) 5073-5078 (2020)

Limits of the detection of microplastics in fish tissue using stimulated Raman scattering microscopy

Moritz Floess, Marie Fagotto-Kaufmann, Andrea Gall, Tobias Steinle, Ingrid Ehrlich, and Harald Giessen
Biomed. Opt. Express 15(3) 1528-1539 (2024)

Performance assessment of probe-based Raman spectroscopy systems for biomedical analysis

Sean Fitzgerald, Eric Marple, and Anita Mahadevan-Jansen
Biomed. Opt. Express 14(7) 3597-3609 (2023)