色谱

色谱 ›› 2022, Vol. 40 ›› Issue (3): 273-280.DOI: 10.3724/SP.J.1123.2021.08005

• 研究论文 • 上一篇    下一篇

高效液相色谱-串联质谱法快速同时测定土壤中草甘膦、草铵膦及其代谢物

平华1,2, 赵芳1, 李成1, 王北洪1, 孔红玲1, 李杨1, 马智宏1,*()   

  1. 1.北京市农林科学院北京农业质量标准与检测技术研究中心, 北京 100097
    2.农业农村部农产品质量安全风险评估实验室(北京), 北京 100097
  • 收稿日期:2021-08-06 出版日期:2022-03-08 发布日期:2022-03-04
  • 通讯作者: 马智宏
  • 基金资助:
    北京市农林科学院青年科研基金(QNJJ202116);北京市农林科学院质标中心自立课题(ZBZXCX201901);北京市农林科学院创新能力建设专项(KJCX20200302)

Rapid and simultaneous determination of glyphosate, glufosinate, and their metabolites in soil by high performance liquid chromatography-tandem mass spectrometry

PING Hua1,2, ZHAO Fang1, LI Cheng1, WANG Beihong1, KONG Hongling1, LI Yang1, MA Zhihong1,*()   

  1. 1. Beijing Research Center for Agricultural Standards and Testing, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China
    2. Risk Assessment Laboratory for Agro-products Quality and Safety (Beijing), Ministry of Agriculture and Rural Affairs, Beijing 100097, China
  • Received:2021-08-06 Online:2022-03-08 Published:2022-03-04
  • Contact: MA Zhihong
  • Supported by:
    Youth Scientific Funds of Beijing Academy of Agriculture and Forestry Sciences(QNJJ202116);Independent Project of BRCAST of Beijing Academy of Agriculture and Forestry Sciences(ZBZXCX201901);Construction Project of Science and Technology Innovation Capacity of Beijing Academy of Agriculture and Forestry Sciences(KJCX20200302)

RichHTML

52

PDF

216

摘要：

建立了快速同时测定土壤中草甘膦(GLY)、草铵膦(GLUF)及其代谢物的高效液相色谱-串联质谱(HPLC-MS/MS)分析方法。分别对前处理和色谱-质谱条件进行优化,样品采用0.5 mol/L氨水作为溶剂振荡提取,离心,上清液过滤膜后,直接采用HPLC-MS/MS测定,电喷雾离子源(ESI-),多反应监测(MRM)模式下检测,外标法定量。结果表明,采用Dikma Polyamino HILIC色谱柱(150 mm×2.0 mm, 5 μm)进行分离,目标化合物峰形良好,响应值高。GLY及其代谢物氨甲基膦酸(AMPA)在5.0~500 μg/L范围内线性关系良好;GLUF及其代谢物N-乙酰基-草铵膦(NAG)、3-(甲基膦基)丙酸(MPP)在2.0~500 μg/L范围内线性关系良好;5种化合物的相关系数(r2)均大于0.998,可以满足定量分析的要求。GLY、GLUF及其代谢物的方法检出限(LOD)在2.0~4.0 μg/kg之间,方法定量限(LOQ)在6.7~13.3 μg/kg之间。在空白土壤样品中添加0.02、0.05、0.2 mg/kg 3个水平的5种化合物混合标准溶液考察回收率,结果表明,低有机质含量土壤中5种化合物的平均加标回收率在74.2%~101%之间,相对标准偏差(RSD)在0.93%~6.8%之间;高有机质含量土壤中5种化合物的平均加标回收率在90.8%~116%之间,RSD在0.40%~7.1%之间。采用建立的方法对实际土壤样品进行测定,AMPA、GLY、MPP、GLUF、NAG的检出率分别为45%、25%、10%、5%和5%,最大残留量分别为147、35.2、154、21.6和11.0 μg/kg,说明土壤中GLY、GLUF及其代谢物残留需要引起一定的关注。该方法简化了前处理步骤,具有简单、快速、绿色环保、成本低、准确度和灵敏度高、重现性好等优点,适用于大批量不同有机质含量土壤样品的检测,为研究其在土壤中的残留状况和环境行为提供了可靠的技术支持。

关键词: 高效液相色谱-串联质谱, 草甘膦, 草铵膦, 代谢物, 土壤, 非衍生化

Abstract:

Glyphosate (GLY) and glufosinate (GLUF) are non-selective translocated herbicides that are used in agricultural and non-agricultural land worldwide. The extensive use of GLY and GLUF may lead to their accumulation in soil, which causes soil pollution and affects the soil micro-ecological environment; the accumulated GLY and GLUF also migrate to groundwater via leaching. However, GLY, GLUF, and their metabolites are highly water-soluble and lack chromogenic and fluorescent groups, making them difficult to analyze. Currently, derivatization methods are mostly used to detect GLY, GLUF, and their metabolites. However, these methods also have some drawbacks, such as complex operation, long time consumption, and poor stability. In addition, these compounds are easily passivated and made inactive in soil; they also react with organic matter, humic acid, metal oxides, and heavy metal ions, making their extraction from soil difficult. To date, the method for the determination of GLY, GLUF, and their metabolites in soil is limited. Therefore, it is necessary to establish a quick and sensitive method to determine the residues of GLY, GLUF, and their metabolites in soil.
In this study, a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the determination of GLY, GLUF, and their metabolites in soil. Parameters like extraction solvent, extraction temperature, extraction time, and adsorbents, which affected the extraction efficiencies, were optimized. Finally, the soil samples were extracted with 0.5 mol/L ammonia solution in a bath shaker at 50 ℃, and then centrifuged at 10000 r/min for 5 min. The supernatant was filtered through 0.2-μm syringe filters and then determined by HPLC-MS/MS. A Dikma Polyamino HILIC column (150 mm×2.0 mm, 5 μm) was used for chromatographic separation with good peak shape and high response of the target compounds. Ammonium acetate (0.2 mmol/L) with 0.07% ammonia aqueous solution and acetonitrile were used as the mobile phase. The flow rate of the elute was 0.25 mL/min. MS/MS was conducted under multiple reaction monitoring (MRM) mode using an electrospray ionization (ESI) source, and was quantified by the external standard method using matrix-matched calibration curves. All the target compounds were ionized in the negative ionization mode. The linear ranges of GLY and its metabolites were between 5.0 and 500 μg/L, and those of GLUF and its metabolites were between 2.0 and 500 μg/L. Linear correlation coefficients were greater than 0.99. The limit of detection (LOD) and limit of quantification (LOQ) were assessed using signal-to-noise (S/N) ratios of 3 and 10, respectively. The LOD and LOQ values of both GLY and (aminomethyl)phosphonic acid (AMPA) were 4.0 and 13.3 μg/kg, respectively. The LOD and LOQ values of GLUF, MPP, and N-acetyl glufosinate (NAG) were 2.0 and 6.7 μg/kg, respectively. Method accuracy was acquired by recovery test at three spiked levels (0.02, 0.05, 0.2 mg/kg). The average recoveries of five targets spiked in soil with low organic matter content were 74.2%-101%, and the relative standard deviation (RSD) was 0.93%-6.8%; the average recoveries of the five targets spiked in soil with high organic matter content were 90.8%-116%, and the RSD was 0.40%-7.1%. The established method was used to determine 20 soil samples in peach orchard, and the detection rates of AMPA, GLY, MPP, GLUF and NAG were 45%, 25%, 10%, 5% and 5%, respectively. The maximum residues were 147, 35.2, 154, 21.6 and 11.0 μg/kg, respectively. This method is simple, rapid, green, inexpensive, allows pretreatment without organic reagents, and affords high accuracy, high sensitivity, and good reproducibility. The method is suitable for testing a large number of soil samples with different organic matter contents. It can provide reliable technical support for the study of residue status and environmental behavior in soil.

Key words: high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), glyphosate, glufosinate, metabolites, soil, non-derivatization

中图分类号: