改进QuEChERS方法结合气相色谱串联质谱检测黄瓜中的邻苯二甲酸酯类

目的建立Fe_3O_4磁性纳米材料QuEChERS结合气相色谱串联质谱联用仪检测黄瓜中15种邻苯二甲酸酯类残留的方法。方法样品采用乙腈超声提取,经无水MgSO_4和NaCl盐析离心后,通过Fe_3O_4磁性纳米材料结合C_(18)和GCB吸附剂净化,采用气相色谱串联质谱MRM模式测定。结果在20~2000μg/kg范围内线性关系良好(r~2≥0.9985),检出限(S/N=3)为0.37~1.58μg/kg。进行了20、50和200μg/kg3个添加浓度的15种邻苯二甲酸酯类的回收率试验,回收率在84.9%~111.6%;RSD为0.41%~6.84%。结论该方法准确、灵敏,符合多残留检测和痕量分析的技术要求,适用黄瓜等蔬菜中邻苯二甲酸酯类残留的分析。

Determination of 15 kinds of phthalate esters in cucumber using gas chro-matography-tandem mass spectrometry with QuEChERS method

Objective To establish a method based on QuEChERS sample preparation method with Fe3O4 magnetic nanoparticles as the absorbing material and gas chromatography-tandem mass spectrometry (GC-MS/MS) for the determination of 15 kinds of phthalate esters residues in cucumber. Method The samples were extracted by ultrasound (homogeneity) using acetonitrile, and then salted out with sodium chloride and anhydrous magnesium sulfate. The supernatant was purified by C18, Fe3O4 magnetic nanoparticles and gra-phitized carbon black (GCB) sorbents, and detected by GC-MS/MS with multiple reaction monitoring (MRM) mode. Results Under the optimum conditions, a good linearity was obtained in the range of 20~2000 ug/kg with correlation coefficients ranging from 0.9985 to 1, and the detection limit(S/N=3)ranging from 0.37 to 1.58 ug/kg. Recovery data were obtained for 15 kinds of phthalate esters spiked into sample extracts at concentrations of 20, 50 and 200 ug/kg. The average recoveries of the phthalate esters ranged from 84.9% to 111.6% and the relative standard deviation (RSD) ranged from 0.41% to 6.84%. Conclusion This method is accurate and sensitive to meet the requirements of multiple residues determination, and can be applied in the analysis of phthalate esters residues in vegetables.