Advanced tools and methodologies for identification, characterization, and quantification of micro/nano plastics in environmental matrices

Although plastics were a ground-breaking invention that transformed modern life, their widespread mismanagement and accumulation have led to pervasive pollution, with microplastics (MPs) and nanoplastics (NPs) now posing risks to ecosystems and human health. This reality is drawing urgent research attention toward their isolation, identification, and quantification in the environment, which is not well-established yet. Therefore, to cover this gap, this review article provides a comprehensive overview of various separation methods, including density separation, oil separation, electrostatic separation, magnetic separation, elutriation, membrane filtration, enzymatic treatments, and sieving. These methods are useful for separating MPs from their surrounding environment. Furthermore, the present work discusses the recent methodologies/techniques employed for the identification and characterization of MPs/NPs in environment, including Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), laser direct infrared (LDIR), pressurized fluid extraction (PFE), thermal analysis, electrochemical sensing, optical sensing, chromatographic techniques, and visual inspection. These techniques are effective in detecting MPs and are widely used to analyse their polymer composition, size, morphology, and shape. This review further outlines recent developments in MPs/NPs identification & quantification methods, major challenges, toxicological mechanism, regulation framework and also, compare their detection limit, cost, accessibility advantages and addresses the limitations associated with various available analytical tools. Overall, this review offers an overview of the various methods for separating, identifying, and quantifying MPs, and underscores the need for continuous innovation required for the advancements and addressing the challenges in the field.