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Determination of Polycyclic Aromatic Hydrocarbons in Traditional Chinese Medicines by Isotope Dilution gas Chromatography-Tandem Mass Spectrometry

OBJECTIVE To develop a GC-MS / MS method for the determination of the residues of 16 polycyclic aromatic hydrocarbons( PAHs) in Chinese herbal medicines. METHODS Using isotope as internal standard,the sample was extracted by ethyl acetate and purified by solid phase extraction on C18 cartridges. GC-MS / MS method was used for the assay,with analyte protectants added to counteract the matrix effect. The chromatographic column was DB-5ms( 0. 25 mm × 30 m,0. 25 μm) with temperature programming and MRM detection. RESULTS The calibration curves for the 16 kinds of typical PAHs were linear in the range of 1- 100ng·m L- 1. The average recovery rate was 88. 53%- 119. 03% in the range of 1- 25 μg·kg- 1with RSDs of 1. 25%- 14. 70%( n =3). The LOQs were 0. 2- 1 μg·kg- 1. CONCLUSION This method is specific,sensitive,accurate and can be used for residue detection of 16 typical kinds of PAHs in Chinese herbal medicines.