Analysis of Single Sub-Millimeter Microplastic Particles by Capillary Size Exclusion Chromatography

Abstract

In recent years, microplastics (MPs) have emerged as a significant environmental concern. The degradation state of MPs in the actual environment varies for each microparticle. For a comprehensive risk assessment of MPs, it is crucial to evaluate diversity at the individual particle level and to analyze measured properties statistically. In this study, we developed capillary size-exclusion chromatography (capillary SEC, inner diameter 0.250 mm × 480 mm) to analyze the molecular weight distribution of MPs at the single-particle level. Additionally, we devised a method for handling single particles to measure samples at the single-particle level using a sampling capillary (inner diameter 0.150 mm × 80 mm). We successfully demonstrated the analysis of a single polystyrene particle with a diameter of 90 μm.