气相色谱-质谱法测定植物油中壬基酚含量

Determination of 4-nonylphenol in vegetable oil by gas chromatography-mass spectrometry

中文关键词:  壬基酚  植物油  衍生  同位素内标  气相色谱-质谱法

英文关键词:4-nonylphenol  vegetable oil  derivatization  isotope internal standards  gas chromatography-mass spectrometry

中文摘要:

      目的 建立气相色谱-质谱法(gas chromatography-mass spectrometry, GC-MS)检测植物油中壬基酚(4-nonylphenol, 4-NP)的分析方法, 了解市售植物油中壬基酚的污染状况。方法 样品加入乙腈提取液, 超声提取、固相萃取柱净化、七氟丁酸酐衍生化后, 采用GC-MS进行检测, 同位素内标法定量。结果 在线性范围5~200 μg/kg内, 方法回归方程为Y=7.78×10?3X, 相关系数为0.9991。方法的检出限为3.0 μg/kg, 定量限 9.8 μg/kg。加标回收率范围为75.7%~107.4%, 相对标准偏差(relative standard deviation, RSD)为5.5%~9.7%。共检测50份市售植物油样品, 其中26份植物油样品检出4-NP, 检出率为52%, 含量范围为3.21~28.2 μg/kg, 中位值为3.63 μg/kg。结论 此方法灵敏度较高, 可用于植物油中4-NP的准确定量。检测数据表明, 植物油样品壬基酚检出率较高, 因此对其含量的监测不容忽视。

英文摘要:

      Objective To establish a method for the determination of 4-nonylphenol (4-NP) in vegetable oil by gas chromatography-mass spectrometry (GC-MS), and to understand the pollution status of 4-NP in vegetable oil. Methods The samples were extracted with acetonitrile by ultrasound, purified by solid phase extraction column, and derivatized with heptafluorobutyric anhydride. The samples were detected by GC-MS and quantified by isotope internal standard method. Results In the linear range of 5?200 μg/kg, the regression equation was Y=7.78×10?3X, and the correlation coefficient was 0.9991. The limit of detection was 3.0 μg/kg and the limit of quantitation was 9.8 μg/kg. The recoveries ranged from 75.7% to 107.4%, and the relative standard deviations (RSDs) ranged from 5.5% to 9.7%. Totally 50 commercial vegetable oil samples were detected, 4-NP was detected in 26 samples, the detection rate was 52%, the content range was 3.21?28.2 μg/kg, and the median value was 3.63 μg/kg. Conclusion This method is simple and sensitive, and can be used for the accurate determination of 4-NP in vegetable oil. The detection data showes that the detection rate of nonylphenol in vegetable oil samples is high, so the monitoring of its content should not be ignored.