气相色谱-质谱法测定植物油中壬基酚含量

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5~200μg/kg内,方法回归方程为Y=7.78×10~(-3)X,相关系数为0.9991。方法的检出限为3.0μg/kg,定量限9.8μg/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3.21~28.2μg/kg,中位值为3.63μg/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。

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

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?200μg/kg,the regression equation was Y=7.78×10?3X,and the correlation coefficient was 0.9991.The limit of detection was 3.0μg/kg and the limit of quantitation was 9.8μg/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?28.2μg/kg,and the median value was 3.63μg/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.