色谱 ›› 2012, Vol. 30 ›› Issue (09): 889-895.DOI: 10.3724/SP.J.1123.2012.04024

• 研究论文 • 上一篇    下一篇

茶叶中氟虫腈等8种农药残留的液相色谱-串联质谱法测定及不确定度评定

胡贝贞1*, 蔡海江2, 宋伟华1   

  1. 1. 绍兴出入境检验检疫局, 浙江 绍兴 312000; 2. 绍兴市水环境科学研究院有限公司, 浙江 绍兴 312000
  • 收稿日期:2012-04-16 修回日期:2012-07-09 出版日期:2012-09-28 发布日期:2012-09-20
  • 通讯作者: 胡贝贞,硕士,工程师,主要研究方向为食品安全. E-mail: huebizhen_002@yahoo.com.cn.
  • 基金资助:

    浙江出入境检验检疫局项目(ZK200993X).

Determination of eight pesticide residues in tea by liquid chromatography-tandem mass spectrometry and its uncertainty evaluation

HU Beizhen1*, CAI Haijiang2, SONG Weihua1   

  1. 1. Shaoxing Entry-Exit Inspection and Quarantine Bureau, Shaoxing 312000, China; 2. Institute of Shaoxing Water Environmental Science Co., Ltd., Shaoxing 312000, China
  • Received:2012-04-16 Revised:2012-07-09 Online:2012-09-28 Published:2012-09-20

摘要: 建立了茶叶中氟虫腈、吡虫啉、啶虫脒、噻嗪酮、三唑酮、三唑醇、丙溴磷、哒螨酮共8种农药残留的液相色谱-串联质谱(HPLC-MS/MS)测定方法。样品用丙酮-二氯甲烷(1:1, v/v)混合溶剂加速溶剂提取,经石墨化炭黑/氨基(Carb/NH2)固相萃取小柱净化,采用Hypersil Gold C18色谱柱(150 mm×2.1 mm, 5 μm)分离,以乙腈-0.1%甲酸水溶液为流动相梯度洗脱,以电喷雾电离(ESI)、多反应监测(MRM)模式检测,采用基质标准曲线同位素内标法(吡虫啉、啶虫脒)或外标法(其余6种农药)定量。氟虫腈在1~100 μg/L、其余7种农药在5~200 μg/L范围内线性关系良好,方法的定量限(信噪比大于10)为氟虫腈2 μg/kg、其余7种农药10 μg/kg。氟虫腈在2、5、50 μg/kg、其余7种农药在10、50、100 μg/kg加标水平下的回收率为75.5%~115.0%,相对标准偏差为2.7%~7.7%。另外,按照JJF 1059-1999《测定不确定度评定与表示》中的有关规定,从标准溶液、样品称量、标准曲线、样品定容、仪器测定重复性、样品前处理等方面对测定结果的不确定度来源进行了评定。评定结果显示,测定结果的不确定度主要源于样品前处理、标准曲线及仪器测定的重复性。该方法的提取效果好、净化较彻底,灵敏度满足国外限量标准的要求,适合出口茶叶中农药残留的测定。

关键词: 不确定度评定, 茶叶, 农药残留, 液相色谱-串联质谱

Abstract: A method was developed for the determination of eight pesticide residues (fipronil, imidacloprid, acetamiprid, buprofezin, triadimefon, triadimenol, profenofos, pyridaben) in tea by liquid chromatography-tandem mass spectrometry. The sample was extracted by accelerated solvent extraction with acetone-dichloromethane (1:1, v/v) as solvent, and the extract was then cleaned-up with a Carb/NH2 solid phase extraction (SPE) column. The separation was performed on a Hypersil Gold C18 column (150 mm×2.1 mm, 5 μm) and with the gradient elution of acetonitrile and 0.1% formic acid. The eight pesticides were determined in the modes of electrospray ionization (ESI) and multiple reaction monitoring (MRM). The analytes were quantified by matrix-matched internal standard method for imidacloprid and acetamiprid, by matrix-matched external standard method for the other pesticides. The calibration curves showed good linearity in 1~100 μg/L for fipronil, and in 5~200 μg/L for the other pesticides. The limits of quantification (LOQs, S/N>10) were 2 μg/kg for fipronil and 10 μg/kg for the other pesticides. The average recoveries ranged from 75.5% to 115.0% with the relative standard deviations of 2.7%~7.7% at the spiked levels of 2, 5, 50 μg/kg for fipronil and 10, 50, 100 μg/kg for the other pesticides. The uncertainty evaluation for the results was carried out according to JJF 1059-1999 “Evaluation and Expression of Uncertainty in Measurement”. Items constituting measurement uncertainty involved standard solution, weighing of sample, sample pre-treatment, and the measurement repeatability of the equipment were evaluated. The results showed that the measurement uncertainty is mainly due to sample pre-treatment, standard curves and measurement repeatability of the equipment. The method developed is suitable for the conformation and quantification of the pesticides in tea.

Key words: pesticide residues, tea, uncertainty evaluation, liquid chromatography-tandem mass spectrometry (LC-MS/MS)

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