Emerging extraction, detection and quantification techniques of environmental concentration micro/nanoplastics in aquatic systems: A critical review

Micro/nanoplastics (MNPs) pose significant threats to the ecological environment and human health, necessitating effective control measures. The small particle size, stability, and dispersibility of MNPs present considerable challenges for accurate detection in aquatic environments. Efficient capture of MNPs is essential for precise detection, and when combined with advanced detection technologies, it enables rapid, in situ analysis in aquatic environments. This review summarized current methods for MNP capture and enrichment in aquatic environments, including membrane filtration, adsorbents, biorecognition, and microrobots. While traditional techniques such as Fourier-transform infrared spectroscopy, Raman spectroscopy, and pyrolysis gas chromatography–mass spectrometry are widely used, they rely on expensive, complex equipment and require cumbersome pre-treatment processes, limiting the ability to achieve high-throughput, non-destructive, rapid detection. Even compared to traditional methods, the applicability and analytical robustness of emerging technologies such as fluorescence-based imaging, surface-enhanced Raman spectroscopy (SERS), and recognition molecule-based sensor, remain strongly dependent on sample type and environmental matrix. However, they still hold significant potential for rapid, in situ detection applications. Moreover, coupling machine learning and data-driven modeling with fluorescence, SERS, and recognition molecule-based sensor, while strongly contingent on representative training datasets and cross-matrix external validation, still offers a promising route to improve identification and quantification accuracy and analytical throughput in complex environmental matrices. This review provides theoretical support for the innovation and development of MNP detection technologies and offers technical guidance for future research on MNP distribution, risk assessment, and control in various aquatic environments.