高效液相色谱-质谱法检测水稻中吡嘧磺隆残留量方法研究

Determination of Pyrazosulfuron-ethyl Resides in Rice by High Performance Liquid Chromatography-tandem Mass Spectrometry

本文采用液相色谱-质谱联用快速分析方法,来检测吡嘧磺隆在水稻植株、土壤残留动态,探究液相色谱-质谱的灵敏度、准确度和可靠性。本文采用Qu ECHERS方法进行样品快速前处理,样品经乙腈提取,PSA、C18吸附剂净化,C18色谱柱分离,0.2%甲酸水∶乙腈等度洗脱,质谱采用电喷雾正离子(ESI+)模式电离,多反应离子监测模式定性分析,基质标匹配外标法定量。在0.02~0.1mg/kg浓度范围内,在不同基质中的吡嘧磺隆的线性相关系数均>0.990 7。在3个浓度添加水平范围内,土壤、水稻植株、稻壳和糙米样品中吡嘧磺隆的平均回收率在78.4%~100.3%之间,相对偏差为1.80%~14.9%。该方法简单、快速、灵敏度高、准确度好,能够满足水稻及土壤中吡嘧磺隆残留量的检测要求。

A rapid analytical method to detect Pyrazosulfuron-ethyl residue in paddy soil, rice plant, rice husk and brown rice was developed using liquid chromatography-tandem mass spectrometry( LC-MS/MS), and the sensitivity, accuracy and reliability of the method was explored. The sample was extracted by acetonitrile and purified by primary secondary amine(PSA)and C18, and then separated on a reversed phase C18 column using an isocratic elution program of0.2% aqueous formic acid and acetonitrile. Qualitative analysis was performed using electrospray ionization in positive mode(ESI+) under multiple reaction monitoring( MRM) mode. Matrix-matched calibrations were respectively used to quantify the residue concentrations. During the concentration range of 1~500μg/g, the matrix-matched calibration curves showed good linearity with determination coefficients >0.990 7. The average recoveries of pyrazosulfuron-ethylin different matrices were in the range of 78.4%~100.3% at spiked levels from 0.02~0.1mg/kg, with relative standard deviations of 1.80%~14.9%(n=5). The method is simple, rapid, sensitive and accurate, which can meet the detection requirements of pyrazosulfuron-ethyl residues in soil and rice.