固相萃取/超高效液相色谱-串联质谱法分析乙烯利在棉籽、棉叶和土壤中的残留

建立固相萃取/超高效液相色谱-串联质谱(SPE/UPLC-MS/MS)检测棉籽、棉叶和土壤中乙烯利残留的分析方法。各基质经甲醇-1%甲酸提取,Oasis MAX色谱柱净化,Cortecs Hilic超高效液相色谱柱进行分离,电喷雾负离子多重反应监测(MRM)模式进行测定。结果表明:在0. 02～1. 94 mg/L范围内,乙烯利在溶剂和各基质提取液中的峰面积与其对应的质量浓度间线性关系均良好,r^2≥0. 996 3;方法的检出限为0. 01mg/kg,定量下限为0. 02 mg/kg;在0. 02、0. 194、3. 88 mg/kg加标水平下,乙烯利在3种基质中的回收率为78. 3%～95. 1%,相对标准偏差(RSD)为1. 9%～5. 2%。该方法具有操作简单、重复性好、灵敏度高等特点,适用于棉籽、棉叶和土壤中乙烯利残留的检测。

Determination of Ethephon Residues in Cotton Seed,Cotton Leaf and Soil by Solid Phase Extraction/Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectrometry

A simple and sensitive method was developed for the determination of ethephon residues in cotton seed,cotton leaf and soil by solid phase extraction/ultrahigh performance liquid chromatography-tandem mass spectrometry(SPE/UPLC-MS/MS).The samples were extracted with methanol-0.1%formic acid,purified with an Oasis MAX column,and separated on a Cortecs Hilic column,finally analyzed in multiple reaction monitoring(MRM)mode via negative electrospray ionization(ESI^-).Under the optimum condition,the calibration curves for the analyte were linear in the range of 0.02-1.94 mg/L,with correlation coefficients(r^2)not less than 0.996 3.The limits of detection and quantitation for ethephon were 0.01 and 0.02 mg/kg,respectively.At spiked levels of 0.02,0.194 and 3.88 mg/kg,the recoveries for ethephon in three matrices were in the range of 78.3%-95.1%with relative standard deviations(RSDs)of 1.9%-5.2%.With the advantages of simplicity,high sensitivity,and good repeatability,the method could satisfy the requirements for determination of ethephon in cotton seed,cotton leaf and soil.