Pretreatment, identification and quantification of submicro/nano-plastics in complex environmental matrices

Submicro/nano-plastics (subμ-NPs, <1 μm), as emerging environmental contaminants, are gaining increasing attention worldwide since they are easier ingested by organisms and might to pose higher environmental risk comparing to microplastics. Although different methodologies have been explored for subμ-NP analysis, a high-efficient and standard method is still lacking. This contribution reviews the progress on pretreatment, identification and quantification of environmental subμ-NPs, the limits of current methodologies and future considerations. Most studies use standard subμ-NPs spiked in environmental samples to explore the applicability of current analytical methods. The ultrafiltration and cloud-point extraction coupled with Raman and mass spectrometry are commonly applied. However, applications of these methodologies are challenging in detection of subμ-NPs from complicate field samples due to unstable detection limits, time consumption, interference of environmental substances and non-label of environmental subμ-NPs. Therefore, more efforts should be made for developing high-efficient, ultra-accurate and standard methodologies of subμ-NP analysis in various environmental matrices.