Quantitative evaluation of silver nanoparticle migration from polyethylene-based packaging and their transformation in simulated gastrointestinal fluids by single particle ICP-MS

Abstract

The increasing use of silver nanoparticles (AgNPs) in food packaging materials for their antimicrobial properties has raised concerns regarding their potential migration into food. To address the analytical challenges of detecting and quantifying AgNPs in food-related matrices, we employed single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) for the simultaneous determination of particle size, number concentration, and dissolved silver content. Polyethylene-based food packaging materials including low-density polyethylene (LDPE), high-density polyethylene (HDPE), and ethylene-octene copolymer (EOC), containing AgNPs were incubated in food simulants (water, 3 % acetic acid, and 10 % ethanol) under various storage conditions (1, 7, and 10 days at ambient and refrigerated temperatures, and 2 h at 70 °C). Migration behavior was evaluated using both SP-ICP-MS and conventional ICP-MS for total silver content. Among the simulants tested, 3 % acetic acid induced the highest silver migration, with temperature significantly enhancing nanoparticle release. Additionally, in vitro gastrointestinal simulations were conducted to assess the transformation of AgNPs after ingestion, revealing aggregation in gastric fluid and disaggregation in intestinal conditions. This work highlights the analytical capability of SP-ICP-MS for monitoring nanoparticle release from food contact materials and offers insight into their physicochemical changes under simulated biological conditions.