Single-Particle Nanoplastic Identification by Liquid-Liquid Interfacial Assembly for Correlative SERS-SEM/EDX

Area of Science:

• Environmental Science
• Analytical Chemistry
• Materials Science

Background:

• Assessing nanoplastic environmental fate and risks is hindered by challenges in analyzing their chemical composition and particle morphology.
• Existing analytical techniques struggle to provide comprehensive characterization of nanoplastics in complex environmental samples.

Purpose of the Study:

• To develop a novel liquid-liquid interface separation strategy for in situ enrichment and simultaneous characterization of nanoplastics.
• To enable the correlation of nanoplastic chemical composition with their morphology for improved environmental risk assessment.

Main Methods:

• A liquid-liquid interface separation strategy was employed to enrich nanoplastics and simultaneously construct surface-enhanced Raman scattering (SERS) substrates using silver nanoparticles (Ag NPs).
• The method integrates SERS with colocalized scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) for comprehensive analysis of individual nanoplastics.
• Nanoplastic enrichment efficiency exceeded 95% for particles sized 100-800 nm in dilute suspensions.

Main Results:

• The developed method achieved high enrichment efficiency (>95%) for nanoplastics while preserving their original morphology.
• Simultaneous determination of chemical composition and morphology of individual nanoplastics was achieved.
• The platform successfully identified and characterized nanoplastics (e.g., PE, PS) in environmental water samples from the Lhasa River.

Conclusions:

• The integrated SERS, SEM, and EDX platform provides a versatile tool for trace detection and comprehensive characterization of nanoplastics in complex matrices.
• This approach offers critical insights into nanoplastic environmental transformation and associated risks.
• The method facilitates a deeper understanding of nanoplastic behavior and impact in aquatic environments.