优化气相色谱-质谱法测定水果和蔬菜中五氯硝基苯残留量的前处理方法

Optimization of pretreatment method for determination of nitrobenzene residues in fruits and vegetables by gas chromatography-mass spectrometry

中文关键词:  水果  蔬菜  五氯硝基苯  气相色谱-质谱联用

英文关键词:fruits  vegetables  quintozene  gas chromatography-mass spectrometry

中文摘要:

      目的 建立检测水果和蔬菜中五氯硝基苯残留量的气相色谱-质谱联用方法。方法 样品采用3种不同前处理法进行提取净化后, 采用内标法进行定量。优化样品预处理方法, 选择适宜的提取溶剂、最佳的超声和振荡时间, 采用选择性离子扫描模式进行质谱检测。结论 在0.02~0.10 μg/mL添加水平, 经正己烷提取和QuEChERS柱净化处理的样品, 其五氯硝基苯的平均回收率在68.32%～96.82%之间, 相对标准偏差为3.4%～5.9% (n=6)。以信噪比S/N=3计算五氯硝基苯的最低检出限为0.002 mg/kg, 方法的定量限为0.0067 mg/kg (S/N=10)。结论 优化后的前处理方法结果准确、重现性好, 检出限相对较低, 满足水果和蔬菜中五氯硝基苯残留量的检测要求。

英文摘要:

      Objective To optimum the pretreatment method for determination of nitrobenzene residues in fruits and vegetables by gas chromatography-mass spectrometry (GC-MS). Methods Samples were extracted and purified by 3 kinds of different pretreatment methods, and quantified by internal standard method. The sample pretreatment method was optimized, including appropriate extraction solvent, and the best ultrasonic and oscillation time. Selective ion scanning (SIM) mode was used for mass spectrometry detection. Results At the spiked levels of 0.02~0.10 μg/mL, average recoveries of nitrobenzene were 68.32%~96.82%, and the relative standard deviations were 3.4%~5.9% (n=6). The lowest limit of detection of nitrobenzene was 0.002 mg/kg (S/N=3) and the limit of quantification was 0.0067 mg/kg (S/N=10). Conclusions The established method has high accuracy and reproducibility, and the limit of detection is relatively low, which can meet the detection requirements of nitrobenzene residues in fruits and vegetables.