高级检索

    不同前处理方式结合超高效液相色谱-串联质谱法测定当归中30种禁用农药残留量

    Determination of Residues of 30 Banned Pesticides in Angelica Sinensis Radix by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry with Different Pretreatment Methods

    • 摘要: 当归样品经QuEChERS法和固相萃取法处理,浓缩后用60%(体积分数)乙腈溶液稀释,采用超高效液相色谱-串联质谱法(UHPLC-MS/MS)同时测定30种禁用农药残留量。以Agilent ZORBAX SB-C18色谱柱(100 mm×2.1 mm,3.5 μm)为固定相,以含5 mmol·L-1甲酸铵的0.1%(体积分数)甲酸溶液-乙腈为流动相体系进行梯度洗脱;质谱分析中以电喷雾离子源正离子模式扫描,多反应监测模式检测。用基质匹配法绘制工作曲线,外标法定量。结果显示:除涕灭威外,其余农药几乎都存在基质效应;30种禁用农药的质量浓度在一定范围内与其对应的定量离子对峰面积呈线性关系,检出限为0.13~15.06 μg·kg-1(QuEChERS法),0.13~14.77 μg·kg-1(固相萃取法);基质匹配混合标准溶液中30种禁用农药测定值的相对标准偏差(n=6)为1.4%~12%(QuEChERS法),1.0%~13%(固相萃取法);阴性样品中30种禁用农药的加标回收率为60.4%~140%(QuEChERS法),61.0%~144%(固相萃取法);方法用于23批当归样品中禁用农药残留情况筛查,有2批样品中检出禁用农药甲拌磷亚砜,检出量为0.016 0~0.019 7 mg·kg-1,并且QuEChERS法和固相萃取法处理后的测定结果基本一致。

       

      Abstract: Angelica sinensis Radix sample was pretreated by QuEChERS method and solid phase extraction method, and the solution was concentrated and diluted with 60% (φ) acetonitrile solution. The residues of 30 banned pesticides were simultaneously determined by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Agilent ZORBAX SB-C18 column (100 mm×2.1 mm, 3.5 μm) was used as the stationary phase, and 0.1% (φ) formic acid solution containing 5 mmol·L-1 ammonium formate-acetonitrile were used as the mobile phase system for gradient elution. Electrospray ionization with positive ion scanning and multiple reaction monitoring mode were used in the mass spectrometry analysis. Matrix matching method was used to draw working curves, and external standard method was used for quantification. It was shown that almost all the pesticides had matrix effect except aldicarb. Linear relationships between values of mass concentration and peak area of quantitative ion pairs of 30 banned pesticides were kept in definite ranges, with detection limits in the ranges of 0.13-15.06 μg·kg-1 (QuEChERS method) and 0.13-14.77 μg·kg-1 (solid phase extration method). RSDs (n=6) of the determined values of 30 banned pesticides in the matrix matching mixed standard solutions were in the ranges of 1.4%-12% (QuEChERS method) and 1.0%-13% (solid phase extration method). Values of spiked recovery of 30 banned pesticides in negative sample were in the ranges of 60.4%-140% (QuEChERS method) and 61.0%-144% (solid phase extraction method). This method was used to screen the residues of banned pesticides in 23 batches of Angelica sinensis Radix samples, and phorate-sulfoxide was detected in 2 batches of the samples, with detection amounts in the range of 0.016 0-0.019 7 mg·kg-1, and the results of QuEChERS method and solid phase extraction method were basically consistent.

       

    /

    返回文章
    返回