Simultaneous determination of residues of 8 frenquently-used herbicide in rice field water by UPLC-MS/MS
[Aims]Based on solid-phase extraction(SPE)technique combined with ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS),determination method of 8 frenquently-used rice field herbicides(mefenacet,pretilachlor,butachlor,quinclorac,bensulfuron-methyl,pyrazosulfuron-ethyl,penoxsulam and pendimethalin)in paddy water were established.[Methods]The paddy water samples were filtered through filter paper,enriched and concentrated by a C18 solid phase extraction cartridge,and then subjected to gradient elution with 0.1%formic acid water-acetonitrile as the mobile phase,determined by UPLC-MS/MS and quantified by matrix external standard method.[Results]The linearity of the method was good with the correlation coefficients(r)greater than 0.99.The limits of detection(LODs)of the method were in the range of 0.0012-0.025 pg/L.The average spiked recoveries were in the range of 80.33%-90.10%in paddy water matrix with the relative standard deviations(RSDs)in the range of 2.66%-8.21%,which made the method suitable for the determination of the eight herbicide residues in rice water.[Conclusions]All the eight herbicides showed matrix-enhanced effects under the conditions of the method,and the solid phase extraction(SPE)technique was used for clean-up and concentration treatment during the actual residue detection in paddy water.The method with simple pre-processing step,is sensitive,reliable,and suitable for the rapid residue detection of frenquently-used paddy herbicides in paddy water.