Optimization of the QuEChERS extraction method to determine Polycyclic Aromatic Hydrocarbons (PAHs) in powder aerosol particles collected by cyclone

Abstract

Conventional methods for collecting and extracting aerosol particles are challenging in accurately characterizing particle-bound polycyclic aromatic hydrocarbons (PAHs) contamination and conducting cellular exposure studies. Therefore, developing direct aerosol sample collection and simple pretreatment analytical methods is necessary. This study describes the optimization of the QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction method for the determination of PAHs in powder-form environmental standard materials (SRM1944) and proves it is also effective for analyzing PAHs in powder aerosol particle samples collected by cyclone. In this study, we used an I-optimal design response surface method combined with a desirability function to investigate the extraction effect of PAHs under different combinations of QuEChERS extraction factors, including extraction solvent, salt, and clean-up reagent. The optimized conditions of the method were determined using the 2-factor interaction (2FI) model combined with boundary conditions, resulting in acetonitrile/dichloromethane (7:1, v/v), Na2SO4/NaCl (1:1, w/w), and primary and secondary amine (PSA) as extraction solvents, extraction salts, and clean-up reagent, respectively. The optimized method showed good recoveries of PAHs reaching 76%–118% and 85%–121% for SRM1944 and standard solution. The results for cyclone-collected ambient powder aerosol particles extracted by the optimized QuEChERS illustrated that this improved procedure has good PAHs extraction efficiency as the traditional Soxhlet method, while reducing hazardous organic solvents usage, experimental cost (per mg sample) by 97% and sample pretreatment time. Overall, this combination of “powder aerosol particle collection and modified QuEChERS extraction” provides new insight on aerosol sample collection, extraction, and in vitro/in vivo exposure studies.