Determination of 18 Polycyclic Aromatic Hydrocarbons in PM_2.5 by Liquid Chromatography with Accelerated Solvent Extraction

A method was proposed for determination of 18 polycyclic aromatic hydrocarbons (PAHs) identified by GS in Germany by liquid chromatography (LC) with accelerated solvent extraction (ASE). The PM_2.5 sample was extracted by ASE with a mixture of dichloromethane-acetone (1+1) at 100℃ for 5 min, with 2 cycle. The extract was concentrated to about 1 mL, then to near dryness by N₂-blowing, and the residue was made its volume up to 1 mL with acetonitrile. The solution obtained was analyzed with ultraviolet (UV)-fluorescence (FLD) detector, with the mixture of acetonitrile and water in different volume ratios as mobile phase for gradient elution. Acenaphthylene (AcPy) was detected by UV (λ=254 nm), and benzoj fluoranthene (BkF) and the other 16 PAHs were respectively determined by two wavelength channels of FLD. As shown by the results, linear relationships between values of peak area and mass concentration of 18 PAHs were found in the same range of 0.02-1.00 mg·L^-1, and detection limits (3S/N) ranged from 0.005 to 0.018 mg·L^-1. Test for recovery was made by standard addition method, giving results in the range of 83.3%-108%, and RSDs (n=5) ranged from 0.82% to 5.2%.