Magnetic solid-phase extraction based on magnetic multi-walled carbon nanotubes for the determination of polycyclic...

A sensitive and reliable method for determination of polycyclic aromatic hydrocarbons (PAHs) in grilled meat samples was developed and validated. The method is based on magnetic solid phase extraction (MSPE) and GC-MS analysis. Magnetic carbon nanotubes (MCNTs) which have excellent adsorption capabilities, were used as adsorbent to extract PAHs, an important class of carcinogens, from meat samples. To obtain the best extraction yields, the influencing factors, including primary extraction conditions, the amount of adsorbent, adsorption and desorption time, salt addition and desorption solvent were investigated in detail. Under optimized conditions, the LODs and LOQs achieved were in the range of 0.035-0.100 and 0.075-0.200 µg Kg(-1) respectively. The calibration curves were linear (r(2) ≥ 0.988) over the concentration ranges from 0.100 µg Kg(-1) to 250 µg Kg(-1) The relative standard deviations (RSDs) obtained by carrying out intra- and inter-day precision studies were less than 13.7% and 13.9%, respectively which confirms reproducibility of the method. In addition, the recoveries of analyzed PAHs ranged from 81.3% to 96.7% with the RSDs less than 12.7 %. Finally, the established MSPE-GC-MS method was successfully applied to determine PAHs in charcoal grilled/barbecued meat samples. benzo[a]anthracene, benzo[b]fluoranthene, Benzo[a]pyrene and chrysene were detected in beef, lamb and chicken meat samples with the mean cumulative concentration of 4.000, 3.414 and 0.931 µg Kg(-1) respectively. Taken together, the MSPE-GC-MS method developed in current study provides a new option for the determination of PAHs in grilled/barbecued meat samples.