Applications of Raman spectroscopy for microplastic detection and characterization: a comprehensive spectral reference.

Microplastics (MPs), plastic particles smaller than 5 mm, represent an escalating global concern due to their persistence, ubiquity, and potential risks to ecosystems and human health. This review critically examines the application of Raman spectroscopy as a possibly non-destructive vibrational technique for detecting and characterizing MPs in environmental and biological matrices. The main objective is to consolidate Raman spectral signatures of common polymers such as polystyrene, polyester, and polyethylene terephthalate and to evaluate methodological advances that improve analytical precision and detection sensitivity. By summarizing Raman-based approaches across water, sediment, air, and biological tissues, this review identifies major analytical challenges including fluorescence interference and matrix complexity and discusses recent innovations such as coherent anti-Stokes Raman spectroscopy (CARS), surface-enhanced Raman spectroscopy (SERS), and compressive Raman technology (CRT). Overall, this work provides a comprehensive reference for Raman spectral data and offers practical insights to guide future research aimed at advancing MP detection and pollution mitigation.