液相色谱-串联质谱法测定豇豆及其栽培土壤中吡唑萘菌胺及其代谢物和嘧菌酯

Determination of azoxystrobin and isopyrazam residues and its degradation products in cowpea and soil by high performance liquid chromatography-tandem mass spectrometry

中文关键词:  吡唑萘菌胺  嘧菌酯  液相色谱-串联质谱法  豇豆  土壤

英文关键词:isopyrazam  azoxystrobin  liquid chromatography-tandem mass spectrometry  cowpea  soil

中文摘要:

      目的 建立用于豇豆及土壤中吡唑萘菌胺及其代谢物和嘧菌酯残留量检测的液相色谱-串联质谱方法。方法 采用水和乙腈提取匀浆后豇豆和土壤样品, 经N-丙基乙二胺和无水硫酸镁净化, 使用甲醇(A)和0.05%甲酸水(B)作为流动相进行梯度洗脱, 质谱(ESI+)采用多反应监测(multiple reaction monitoring, MRM)对吡唑萘菌胺及其代谢物和嘧菌酯的定量离子和定性离子进行扫描, 结合目标物标准曲线进行定量分析。结果 经过3个水平的添加回收率实验, 建立方法的平均回收率在74%~101%之间, 相对标准偏差0.9%~9.2%(n=5)。吡唑萘菌胺顺式异构体(SYN 534969)、吡唑萘菌胺反式异构体(SYN 534968)、吡唑萘菌胺代谢物一(SYN 545364)、吡唑萘菌胺代谢物二(SYN 545449)和嘧菌酯的仪器检出限分别为0.1、0.1、0.1、0.8和0.03 mg/kg, 加标回收实验得出吡唑萘菌胺代谢物二(SYN 545449)在豇豆和土壤中的最低检出浓度均为0.05 mg/kg, 吡 唑萘菌胺顺式异构体、反式异构体、吡唑萘菌胺代谢物一(SYN 545364)及嘧菌酯的最低检出浓度均为 0.005 mg/kg。结论 该方法简单、快速、准确, 灵敏度高, 适用于豇豆及土壤中吡唑萘菌胺及其代谢物和嘧菌酯残留量检测。

英文摘要:

      Objective To establish a method for simultaneous determination of azoxystrobin and isopyrazam residues and its degradation products in cowpea and soil by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods Cowpea and soil samples after homogenate were extracted by acetonitrile and water, purified by PSA and dehydrated by magnesium sulfate anhydrous, gradient elution using methanol (A) and 0.05% formic acid water (B) as the mobile phase. Quantitative and qualitative ions of pyrazole naphthylamine and its metabolites and cyprolactone were scanned and quantitatively analyzed in combination with the standard curve of the target substance. Results The average recoveries of the method were between 74%-101% for 3 spiked levels, and the relative standard deviations were 0.9%-9.2% (n=5). Instrument limits of detection (LODs) of cis-isomer and trans-isomer of isopyrazam, SYN 545364, SYN 545449 and azoxystrobin were 0.1, 0.1, 0.1, 0.8 and 0.03 μg/kg, respectively. The results of recoveries showed that the lowest detectable concentrations in cowpea and soil were 0.05 mg/kg for SYN 545449, and 0.005 mg/kg for cis-isomer and trans-isomer of isopyrazam, SYN 545364 and azoxystrobin. Conclusion The method is simple, rapid, accurate, and had the advantages of high sensitivity. It is suitsble for the detection of azoxystrobin and isopyrazam residues and its degradation products in cowpea and soil.