High Throughput Method for the Determination of PAHs in Seafood by QuEChERS-SBSE-GC-MS
App Note 6/2010
This method uses a QuEChERS (quick, easy, cheap, effective, rugged, and safe) single-step acetonitrile (ACN) extraction and salting out liquid-liquid partitioning to extract PAHs from seafood tissue. Stir Bar Sorptive Extraction (SBSE) is then used as a combined cleanup and concentration step, eliminating organic acids and other polar and high molecular weight matrix components and providing a substantial concentration factor to easily meet regulatory limits of detection and requirements established for precision and accuracy for determination of PAHs in seafood tissue. In brief, 3g of a homogenized seafood tissue sample in water is extracted with ACN in a 50 mL centrifuge tube followed by addition of 6.0 g MgSO4 and 1.5 g sodium acetate which is shaken and centrifuged. A portion of the ACN extract (upper layer) is added to a 10 mL vial with 4 mL 0.1 M NaHCO3 and a GERSTEL Twister™ stir bar and stirred to extract and concentrate the PAHs. The Twister stir bar is transferred to a thermal desorption tube in an autosampler tray for analysis by gas chromatography/mass spectrometry (GC/MS).