摘要：
建立了水中百草枯和敌草怏的固相萃取/高效液相色谱-串联质谱测定方法.样品直接经Cleanert PWCX小柱富集净化,HILIC亲水型液相色谱柱分离,5 mmol/L乙酸铵用(用甲酸调至pH3.7)-乙腈梯度洗脱,采用电喷雾离子源正离子模式采集,选择性反应监测模式下检测,外标法定量.结果表明,百草枯和敌草快分别在10.0 ～ 200.0μg/L和1.0 ～ 200.0μg/L质量浓度范围内呈良好的线性关系,相关系数(r2)均不小于0.997,在30～ 200 μg/L的加标水平下,百草枯和敌草快的平均回收率分别为96.8％～125.8％和97.2％～118.2％,批内相对标准偏差(RSD)分别为3.0％～6.3％和2.9％～6.0％;批间RSD分别为3.3％ ～ 8.2％和2.7％ ～ 7.9％.以3倍信噪比计算,百草枯和敌草快的方法检出限分别为5.0 μg/L和0.3μg/L;以10倍信噪比计算,方法的定量下限分别为10.0 μg/L和1.0μg/L.该方法简便、快速、灵敏,方法的线性范围、回收率、精密度和检出限均符合残留分析的要求,能满足水中百草枯、敌草快残留监控的要求.%A method was developed for the determination of paraquat and diquat residues in water by high performance liquid chromatography-tandem mass spectrometry with solid phase extraction.The samples were cleaned up by Cleanert PWCX solid phase extraction,separated on a HILIC column using acetonitrile-5 mmol/L ammonium acetate(pH 3.7 with formic acid) as mobile phase by gradient elution,then detected in SRM mode and quantified by external standard method with the matrixmatched calibrations.The calibration curves for paraquat and diquat showed good linearities in the concentration ranges of 10.0-200.0 μg/L and 1.0-200.0 μg/L,respectively,with correlation coefficients(r2) no less than 0.997.The average recoveries for paraquat and diquat in agricultural environmental water at spiked levels of 30-200 μg/L were in the ranges of 96.8％-125.8％ and 97.2％-118.2％,with intra-assay relative standard deviations (RSDs) of 3.0％-6.3％ and 2.9％-6.0％,and inter-assay relative standard deviations of 3.3％-8.2％ and 2.7％-7.9％,respectively.The limits of detection (LODs) and quantitation (LOQs) of the method were 5.0 μg/L and 0.3 μg/L,and 10.0 μg/L and 1.0 μg/L,respectively.The results indicated that the developed method is easy,fast and sensitive,its indicators such as the linear range,recovery,precision and detection limit could meet the requirements for residue analysis.The method is suitable for the determination of paraquat and diquat in agricultural environmental water
