加速溶剂萃取-气相色谱质谱法测定太子参中酰胺类除草剂的含量

建立了太子参中乙草胺、丁草胺和S-异丙甲草胺的加速溶剂萃取-气相色谱/质谱测定的分析方法。对提取溶剂、萃取温度、净化材料、不同冲洗体积和静态萃取时间、循环次数等实验条件进行了优化。用HP-5MS弹性石英毛细管柱经柱程序升温技术分离,并用质谱检测器检测,内标法计算含量。本方法测定太子参中乙草胺、丁草胺和S-异丙甲草胺的检出限分别为0.16 ng/g、0.18 ng/g和0.05 ng/g,精密度分别为2.6%、3.9%和3.1%,回收率为80.2%-104.1%。所测样品不含上述3种除草剂残留。本方法简便、干扰小、检测效果好,可用于太子参药材中此类除草剂残留的分析。

Determination of Three Kinds of Chloroacetanilide Herbicides in Radix Pseudostellariae by Accelerated Solvent Extraction and Gas Chromatography-Mass Spectrometry

A gas chromatographic-mass spectrometry(GCMS) method for the determination of herbicides acetochlor,butachlor and S-metolachlor in Radix Pseudostellariae(Taizishen in Chinese),a widely used Chinese medicinal herb,was developed.The herbicides in the plant samples were extracted by accelerated solvent extraction(ASE).ASE conditions,including extraction solvent,temperature,clean-up reagent,flush volume,static time and static cycle were optimized.The extract was concentrated and then analyzed by GC-MS under select ion monitoring(SIM) mode.The herbicide residues were quantified by internal standard method.The detection limits and relative standard deviations for acetochlor,S-metolachlor and butachlor were 0.16 ng/g,0.05 ng/g,0.18 ng/g,and 2.6%,3.1%,3.9%,respectively.The average recoveries ranged from 80.2 % to 104.1 %.The three target herbicides were not detected in all the samples we analyzed.The method is easy to operation,and with good precision,it is therefore well suited for the routine analysis of herbicides in herb samples such as Radix Pseudostellariae.