| Polycyclic aromatic hydrocarbons(PAHs)are a kind of organic contaminants which could induce cutaneous, scrotum and lung cancer. They widely exist in food and environment, and can be produced in many ways, for example, incomplete combustion of petroleum and coal and emissions of automobile exhaust. This paper established three methods including high performance liquid chromatography with UV detection(HPLC-UV), microemulsion electrokinetic chromatography(MEEKC) and micellar electrokinetic chromatography with field-amplified sample stacking(MEKC-FASS) for PAHs determination in roast meat. Compared the three methods, MEKC-FASS was recommended as a rapid analytic method for PAHs in meat which is important for health security of human being.HPLC method for the determination of 13 PAHs in roast meat was established. The pretreatment procedure were investigated to reduce impurity and avoid the pollution of column. After optimizing, the pretreatment procedure were included: ultrasonic extraction, saponify with 2 mol/L KOH in methanol: water(9:1; v/v)solution, liquid-liquid extraction with cyclohexane, clean-up with C18 SPE and concentrate. Samples were analyzed by HPLC, and the determination conditions were as fllows: column: Nucleodur C18, 5μm, 4.6×250 mm. mobile phase: methanol:water(93.2:6.8; v/v)for isocratic elution; the detection wavelength: 254 nm. This method was of good linearities(R>0.99). LOD of Nap, AcNy, Fl, PhA, An, FlA, Py, BaA, BbF, BkF, BaP, DbahA, BghiP are 6.8μg/L, 8.9μg/L, 0.2μg/L, 0.3μg/L, 0.6μg/L, 0.8μg/L, 1.4μg/L, 0.2μg/L, 1.3μg/L, 0.7μg/L, 0.1μg/L, 0.6μg/L, 0.3μg/L respectively. RSD of inter-day variablity was less than 5%. The method was successfully used for analysis PAHs in roast meat, and recoveries were between 68.5% and 103%.Microemulsion electrokinetic chromatography with UV detection for determination of 6 PAHs was established. In this part samples were pretreated simplely by ultrasonic extraction and C18 SPE, and then analyzed by MEEKC. The MEEKC determination conditions were as follows: non-coating capillary column (65 cm×50μm); microemulsion buffer containing 0.4%(m/m)n-hexane, 1.8%(m/m)SDS, 20%(v/v)butanol, 22%(v/v)acetonitrile and 20 mmol/L pH9.24 borax buffer; pressure injection at 30 mbar/6 s; the detection wavelength of 280 nm; separation voltage of 20 kV; column temperature at 20℃. This method is of good linearities(R>0.99)and precision inter-day variablity(RSD<5%). LOD of FlA, BaA, BbF, BaP, DbahA, BghiP are 1.9μg/mL, 0.7μg/mL, 2.3μg/mL, 1.3μg/mL,2.1μg/mL, 3.4μg/mL respectively. This method is suitable for the analysis of samples with high PAHs content, but not appropriate for samples with low PAHs content.For the low sensitivity of UV detection in CE, the trace-level of PAHs in roast meat could not be detected. So FASS of PAHs was investigated using MEKC. The MEKC-FASS conditions were as follows: non-coating capillary(80 cm×50μm); micellar buffer containing 120 mmol/L SDS, 50%(v/v)acetonitrile and 10 mmol/L NaH2PO4(pH2.50); pressure inject with water at 16 kPa/50 s; electrokinetic injection with sample at -20 kV/54 s; separation voltage: -20 kV; column temperature: 20℃; detection wavelength: 280 nm. This method is of good linearities(R>0.99) and precision inter-day variabilities(RSD<10%). LOD of FlA, BaA, BbF, BaP, DbahA, BghiP was 3.4×10-2μg/mL, 8.6×10-2μg/mL, 6.8×10-2μg/mL, 9.1×10-2μg/mL, 20×10-2μg/mL, 14×10-2μg/mL.Compared the three methods above-mentioned, results showed that both HPLC-UV and MECC-FASS could be used to analyze PAHs in roast meat, and the pretreatment for MECC-FASS was simple and easier to achieve rapid analysis of PAHs in roast meat. Roast meat from market was determinated by MEKC-FASS. Results show that the most carcinogenic PAHs in roast meat sample were all found, and the content of BaP was not exceed the EU'limited indicator for PAHs in smoked meat products.
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