液相色谱-串质谱法测定大米中异噁唑草酮及代谢物残留量

Determination of isoxaflutole and its metabolites residues in rice by liquid chromatography-mass spectrometry/mass spectrometry

中文关键词:  异噁唑草酮及代谢物  液相色谱-串联质谱法  大米

英文关键词:isoxaflutole and its metabolites  liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS)  rice

中文摘要:

      目的 建立大米中异噁唑草酮及代谢物残留量的液相色谱-串联质谱法测定方法。方法 试样中残留的异噁唑草酮除草剂及代谢物用乙酸乙腈溶液(1:99, V:V)高速匀浆提取, 提取液经N-丙基乙二胺(PSA)、十八烷基硅烷(ODS)净化, 经色谱柱为ACQUITY UPLC BEH Phenyl分离和流动相为1.5%乙酸的乙酸铵(1 mmol/L)－乙腈进行梯度洗脱, 用配有大气压化学电离源(APCI)的液相色谱-串联质谱仪检测和确证。结果 异噁唑草酮及代谢物在0.0025~1.000 μg/mL浓度范围内呈现良好线性关系(r=0.9998~0.9999)。当样品加标浓度在5~200 μg/kg 范围内时, 其样品加标平均回收率为70.2%~110.6%, 相对标准偏差为7.38%~12.84%。异噁唑草酮及代谢物的最低检出限分别为10 μg/kg、5 μg/kg。结论 本方法适用于大米中异噁唑草酮及代谢物残留的同时测定。

英文摘要:

      Objective To establish a novel method for determination of isoxaflutole and its metabolites residues in rice by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). Methods With acetic acid acetonitrile solution(1:9,V:V) as the extraction, the test sample were extracted by means of high speed homogenization, cleaned up by primary secondary amine (PSA) and octadecylsilane (ODS). The residues in the extracts were separated on a reversed–phase liquid chromatography with ACQUITY UPLC BEH Phenyl column using a gradient elution program of 1.5% acetic acid (1 mmol/L) ammonium acetate solution and acetonitrile. The residues were determined and confirmed by LC-MS/MS equipped with atmosphere pressure chemical ionization source. Results The calibration curve of isoxaflutole and its metabolites showed a good linearity in the range of 0.0025~1.000 μg/mL with the correlation coefficient of 0.9998~0.9999. The average recoveries of isoxaflutole and its metabolites in spiked samples were in the range of 70.2%~110.6%, and the relative standard deviations (RSD) were between 7.38%~12.84% at spiked levels of 5~200 μg/kg. The limit of detection was 10 μg/kg and 5 μg/kg for the isoxaflutole and its metabolites, respectively. Conclusion This method can be used for the simultaneous determination of isoxaflutole and its metabolites residues in rice.