Nondestructive analysis of plastic debris from micro to nano sizes: A state-of-the-art review on Raman spectroscopy-based techniques

Micro- and nanoplastics pose significant risks to ecosystems and human health, necessitating accurate detection for a comprehensive understanding of their distribution and impact. Despite being widely employed, traditional Raman spectroscopy has limitations in analyzing plastic debris at the submicron and nanoscale or with complex compositions. This review discussed four advanced Raman-based techniques for detecting plastic debris, including surface-enhanced Raman scattering, Raman tweezers, tip-enhanced Raman scattering, and Raman mapping/imaging, along with optimizations and improvements for achieving nanoscale detection in various environmental samples. It addressed the shortcomings and critical challenges faced by each advanced Raman technique and proposed potential solutions and new developments in the detection of micro- and nanoplastics, with the aim of enhancing the effectiveness of environmental monitoring and risk assessment.