饮用水中的9种农药残留及微囊藻毒素的在线固相萃取-液相色谱-质谱法测定

Determination of pesticide residues and microcystin in drinking water using on-line SPE liquid chromatography-mass spectrometry

目的建立饮用水中9种农药残留和微囊藻毒素LR的在线固相萃-取液相色谱-串联质谱(online SPE LC-MS/MS)的检测方法。方法采用在线固相萃取技术,水样经HRP SPE柱富集,HSS T3高效液相色谱柱分离,乙腈和甲酸水梯度洗脱,分别用三重四极杆串联质谱和飞行时间质谱检测,ESI正离子模式下采集数据,外标法定量。结果 10种目标化合物的定量限远低于我国生活饮用水卫生标准的限量要求,其中飞行时间质谱法的LOQ为0.08～0.40μg/L,三重四级杆质谱法的LOQ为0.01～0.19μg/L。3个加标水平下(0.1、0.2、1倍的标准限量),10种目标物的加标回收率为66.5%～130.3%,相对标准偏差为0.8%～14.5%。结论该方法快速、简单、灵敏度高,适用于饮用水中有关农药残留和藻毒素的同时检测。

Objective To develop a method based on on-line solid phase extraction followed liquid chromatography mass spectrometry for determination of 9 pesticides and microcystin-LR in drinking water.Method Drinking water samples were concentrated by a HRP-SPE cartridge and separated on a HSS T3 column with a gradient mobile phase of acetonitrile and aqueous 0.1% formic acid,then analyzed by triple quadrupole mass spectrometry（TQ-MS） and time of flight mass spectrometry（TOF-MS）,respectively.Mass acquisition was conducted under positive electrospray ionization mode.Quantification was performed by external standard calibration.Results The quantification limits（LOQs） of 10 target compounds were far below the limits set by the National Standards for Drinking Water Quality.The LOQs of TOF-MS was 0.01-0.40 μg/L and the LOQs of TQ-MS was 0.01-0.19 μg/L.Recoveries of 10 target compounds were 66.5%-130.3% with relative standard deviation between 0.8% and 14.5%.Conclusion Due to its rapidness,simpleness,and high sensitivity,the method is suitable for the determination of pesticides and microcystin-LR in drinking water.