A one-step, scalable thermospray method for synthesis of multicomponent particles mimicking atmospheric particulate matter

Abstract

The extremely high complexity in composition of PM2.5 poses a major challenge in assessment of its environmental health risks. Laboratory-based toxicological studies are often limited by the scarcity of real environmental PM2.5 samples, which are essential for various analyses. Most conventional sampling procedures yield insufficient amounts of PM2.5 to meet the demands for physicochemical characterization, toxicological evaluation, and replication of findings. Current synthetic models typically consist of single or limited components, lacking the multi-component realism essential for accurate toxicity assessment. Here, we present a novel, facile, and scalable spray-drying method to fabricate multi-component model PM2.5 particles with tunable chemical compositions, closely mimicking real ambient PM2.5 in morphology, size distribution, and elemental profile. We also tested the biological toxicity response of these synthetic particles in vitro. This work provides a robust, reproducible, and accessible tool for particulate toxicology and broader airborne particle research to overcome critical supply and standardization barriers, thus enabling systematic investigation of component interactions, synergistic effects, and source-specific toxicity for advancing environmental health research and risk assessment of PM2.5.