气相色谱-质谱法测定含油脂食品中新型增塑剂对苯二甲酸二辛酯

Determination of New Plasticizer Di(2-ethylhexyl) Terephthalate in Foods Containing Fats and Oil by Gas Chromatography-Mass Spectrometry

摘要:

该研究通过乙腈提取，PSA/硅胶复合固相萃取柱净化，气相色谱-质谱联用仪检测，建立了含油脂类食品中对苯二甲酸二辛酯含量测定的方法。样品采用乙腈超声多次提取，PSA/硅胶复合固相萃取柱净化，流出液经旋转蒸发仪浓缩，经HP-5MS UI毛细管柱分离后，采用SIM模式对样品中的邻苯二甲酸二辛酯进行检测，外标法定量。实验结果表明，对苯二甲酸二辛酯在0.125~2.50 μg/mL范围内，具有良好的线性范围，线性相关系数大于0.99，方法的检出限为0.20 mg/kg，定量限为0.50 mg/kg，在0.50 mg/kg、1.00 mg/kg、5.00 mg/kg 3个添加水平下，样品中对苯二甲酸二辛酯的平均回收率为78.11%~104.53%，相对标准偏差（RSD，n=6）低于7.21%；该方法简单、快速、灵敏，可用于含油脂食品中对苯二甲酸二辛酯的检测，用本研究建立的方法检测40个含油脂类食品，10个样品有检出，涉及芝麻酱、辣椒油、植物油和肉制品，检出含量范围为0.64 mg/kg~1586.34 mg/kg，部分阳性样品含量较高，应当引起我们的重视。

Abstract:

A method was established for determining the di(2-ethylhexyl) terephthalate in foods containing fats and oil, through acetonitrile extraction, PSA/silica composite solid phase extraction column purification, and gas chromatography-mass spectrometry analysis. The samples were subjected to ultrasound-assisted extraction with acetonitrile multiple times and purified by PSA/silica composite solid phase extraction column, concentrated by a rotary evaporator, and separated by HP-5MS UI quartz capillary chromatographic column, before the analysis of di(2-ethylhexyl) terephthalate in the samples by the external standard method under the selected ion monitoring (SIM) mode. The experimental results show that a good linear relationship was found in the di(2-ethylhexyl) terephthalate concentration range of 0.125~2.50 μg/mL, with correlation coefficients higher than 0.99, limit of detection as 0.20 mg/kg, and the limit of quantitation as 0.50 mg/kg. When the spiked levels were 0.50, 1.00 and 5.00 mg/kg, the mean recoveries of di(2-ethylhexyl) terephthalate in foods containing fats and oil ranged between 78.11% and 104.53% with the relative standard deviations (RSD, n=6) not higher than 7.21%. This method is simple, rapid and sensitive, which is suitable for determining the di(2-ethylhexyl) terephthalate in foods containing fats and oil. Among the 40 fat/oil-containing food samples analyzed by the established method, 10 samples involving sesame paste, chili oil, vegetable oil and meat products were found to contain di(2-ethylhexyl) terephthalate (concentration: 0.64 mg/kg~1586.34 mg/kg), in particular, some positive samples had a high content, thereby deserving high attention