The detection of nanoplastics in aquatic ecosystems, which pose environmental and health hazards, incurs significant time and cost penalties. These tiny plastic particles, measuring less than 100 nanometers, are not easily filtered out by traditional water treatment methods and require extensive pre-processing of samples for analysis. Prospects for real-time, cost-effective measurement improve with the advent of an electro-photonic sensing system developed in South Korea.

Analytical capacity is accelerated by use of an electro-photonic tweezer and metal nanoparticles to form a light-based, real-time detection system that concentrates ultrafine nanoplastics within a short time frame. Electricity is supplied to a large-area vertically aligned metal sandwiched by a nanofilm insulator, after which Raman spectroscopy is performed to assess the energy difference between incident and scattered light according to the frequency of the molecule.

Raman-spectroscopy-based nanoplastic detection using the electric-optical tweezer and surface-enhanced Raman scattering. Source: acsnano.2c07933

This approach was demonstrated to achieve detection of a 30 nm 10 μg L^-1 polystyrene particle, which was easily separated from the sample through the dielectrophoresis phenomenon. The collection, separation and analysis steps, which conventionally require at least one day were reduced to several seconds by use of this single platform.

The study conducted by researchers from Korea Institute of Science and Technology and University of Seoul is published in ACS Nano.