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A simple, rapid, and green method was developed for the simultaneous analysis of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and polybrominated biphenyl ethers in aquatic products using subcritical 1,1,1,2-tetrafluoroethane extraction coupled with gas chromatography and mass spectrometry. Effects of the extraction temperature, pressure, and cosolvent volume on the extraction efficiency were investigated by extracting spiked oyster samples. The results show that the maximum extraction efficiency was obtained at 40°C, 12 MPa, and a cosolvent (dichloromethane) volume of 5.0 mL. Under these conditions, the calibration curves had good linearity with square of the correlation larger than 0.998 in the concentration range of 5-800 ng/mL; limit of detection and limit of quantitation were 0.16-2.83 and 0.55-9.43 ng/g, respectively. At spiked levels of 10, 30, and 50 ng/g, the average recoveries were 70.4-80.4% for polycyclic aromatic hydrocarbons, 74.0-83.6% for polychlorinated biphenyls, and 66.9-78.0% for polybrominated biphenyl ethers, with average relative standard deviations of less than 16.3%. The established method has no significant differences in recovery compared to traditional methods and is suitable for the analysis of real samples.
RESUMO
OBJECTIVE: To research the optimal extraction process of supercritical CO2 extraction and analyze the component of the oil extracted from Aesculus wilsonii seed. METHODS: Using the yield of Aesculus wilsonii seed oil as the index, optimized supercritical CO2 extraction parameter by orthogonal experiment methodology and analysed the compounds of Aesculus wilsonii seed oil by GC-MS. RESULTS: The optimal parameters of the supercritical CO2 extraction of the oil extracted from Aesculus wilsoniit seed were determined: the extraction pressure was 28 MPa and the temperature was 38 degrees C, the separation I pressure was 12 MPa and the temperature was 40 degrees C, the separation II pressure was 5 MPa and the temperature was 40 degrees C, the extraction time was 110 min. The average extraction rate of Aesculus wilsonii seed oil was 1.264%. 26 kinds of compounds were identified by GC-MS in Aesculus wilsonii seed oil extracted by supercritical CO2. The main components were fatty acids. CONCLUSION: Comparing with the petroleum ether extraction, the supercritical CO2 extraction has higher extraction rate, shorter extraction time, more clarity oil. The kinds of fatty acids with high amounts in Aesculus wilsonii seed oil is identical in general, the kinds of fatty acids with low amounts in Aesculus wilsonii seed oil have differences.