加速溶剂萃取-固相萃取/超高效液相色谱-串联质谱法测定育苗基质中矮壮素与助状素

Determination of Chlormequat and Mepiquat Residues in Seeding Cultivation Using Accelerated Solvent Extraction-Solid-phase Extraction/Ultra-performance Liquid Chromatography-Tandem Mass Spectrometry

研究建立了一种加速溶剂萃取-固相萃取/超高效液相色谱-串联质谱法(SPE-UPLC-MS/MS)测定育苗基质中矮壮素和助状素的分析方法。样品采用快速溶剂萃取仪(ASE)提取,经CBA弱阳离子交换柱净化后,在亲水作用色谱柱上用SeQuant ZLC-HILIC MEKCK色谱柱进行分离;电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测。矮壮素和助状素的质量浓度在0.2～10μg/kg范围内线性关系良好(r2>0.999),在2、5、10μg/kg加标水平的平均回收率分别为77%～106%和97%～111%,相对标准偏差(RSD)分别为7.3%～21.7%和5.6%～16.1%,检出限(LOD)均为0.02μg/kg,定量下限(LOQ)均为0.1μg/kg。该方法简便、快速、灵敏、准确,适合育苗基质中矮壮素和助状素残留的确证和定量测定。

A method for the determination of chlormequat and mepiquat residues in samples from seeding cultivation products was established by accelerated solvent extraction-solid-phase extraction coupled with ultra-performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）.The samples were extracted with ASE 200 system and cleaned up with weak cation exchange（CBA） column.The identifications of chlormequat and mepiquat were performed on a HILIC column packed with 5 μm particles under isocratic LC conditions by using 0.1% formic acid in 20 mmol/L ammonium acetate（A） and acetonitrile（B）（VA ∶ VB=40 ∶ 60）.The quantification of analytes was achieved by using electrospray ionization under positive ion mode（ESI＋） with multiple reaction monitoring（MRM）.The result indicated that the calibration curves were linear in the range of 0.2-10 μg/kg for both compounds.The average recoveries at spiked concentration levels of 2,5,10 μg/kg ranged from 77% to 111% with relative standard deviations of 5.6%-21.7%.The limits of detection were 0.02 μg/kg and the limits of quantitation were 0.1 μg/kg for both compounds.The established method was simple,rapid,sensitive and specific,and was suitable for the identification and quantification of chlormequat and mepiquat residues in seeding cultivation.