[Determination of 16 polycyclic aromatic hydrocarbons in edible oils by gas chromatography-mass spectrometry combined with molecularly imprinted solid phase extraction].

OBJECTIVE

To establish a method for determination of 16 polycyclic aromatic hydrocarbons( PAHs) in edible oils by gas chromatography-mass spectrometry( GC/MS) combined with molecularly imprinted solid phase extraction( MISPE-GC/MS).

METHODS

Oil samples were diluted with n-hexane, purified by SPE cartridges based on molecularly imprinted polymer. The cartridges were washed by n-hexane to remove impurities, then eluted with dichloromethane. After being concentrated to a volume of 200μL, the analytes were separated by capillary column( 30 m×0. 25 mm×0. 25 μm) and analyzed by GC/MS with selected ion monitoring( SIM) mode. Isotope internal standard method was adopted for quantification.

RESULTS

The 16 kinds of PAHs showed good linearity in the range of 2-20 μg/L( r > 0. 998). The detection limits ranged from 0. 1 to0. 6 μg/kg. The recoveries of spiked samples at the level of 2 μg/kg and 10 μg/kg were in the range of 75. 5%-125. 2%( n = 6), the relative standard deviations( RSD) were all less than 15%.

CONCLUSION

The proposed method is selective, fast, and presentsexcellent purification effect as well as high sensitivity, which makes it capable for rapid determination of 16 PAHs in edible oils with satisfactory accuracy.