Can flow cytometry emerge as a high-throughput technique for micro- and nanoplastics analysis in complex environmental aqueous matrices?

The potential of flow cytometry (FCM) for monitoring micro- and nanoplastics (MNPs) in environmental aqueous matrices was explored. FCM has driven interest due to its rapidity, high sensitivity, and potential for automation. This review explores the current potential of FCM for detecting MNPs in environmental matrices, discussing its advantages and limitations from two perspectives: (1) quantification of naturally occurring MNPs, providing insights into the existing plastic pollution; and (2) analysis of traceable MNPs spiked into water matrices. Fluorescent dyes can be coupled with FCM to stain MNP polymers, and co-staining permits the discrimination of plastics from biological cells. When combined with spiked microspheres, FCM becomes an excellent tool for quasi-real-time monitoring of MNPs, improving knowledge about MNP removal efficiency in engineered systems. Given that no other technique allows for such high-throughput analysis of small MNPs, the use of spiked MNPs represents a paradigm shift for future environmental studies of MNPs.