在线固相萃取-二维高效液相-串联质谱法测定水中微囊藻毒素-LR

摘要

建立了全自动化在线固相萃取-二维高效液相色谱-串联质谱法测定水中微囊藻毒素-LR的新方法.一维液相系统(上样泵)直接将100 μL水样泵送人固相萃取柱富集,六通阀自动切换,另一维液相系统(分析泵)则将微囊藻毒素-LR冲洗至分析柱进行分离检测.试验结果表明,该方法快速、灵敏度高、精密度好,能够满足生活饮用水及其水源水中痕量微囊藻毒素-LR的检测要求,也非常适合突发水质污染时的应急检测.饮用水和水源水中高低两种浓度微囊藻毒素-LR的平均加标回收率分别为99.1％～106.0％和108.4 ％～108.8％,相对标准偏差为2.4 ％～7.0％和1.8 ％～9.4％,微囊藻毒素-LR的检出限为0.002 6 μg/L远低于国标0.06 μg/L的检出限.%A fully automated online solid phase extraction,two-dimensional HPLC-MS/MS method was developed for analyzing the Microcystin-LR concentration in water.Water samples were first pumped by one-dimensional HPLC system (loading pump)to the online SPE column for the water concentration.Then by automatically controlled valve-swich the Microcystin-LR analyzes were back-flushed to the analytical column using another-dimensional HPLC system (analytical pump) for determination.Experimental results show the method is capable of analyzing the Microcystin-LR concentration in drinking water and raw water because of its rapidity,sensibility and high accuracy.Also,it is very suitable for the detection of those unexpected water pollutions.Recoveries of Microcystin-LR concentration for drinking water and raw water are 99.1％～106.0 ％ and 108.4 ％～108.8 ％,respectively.Accordingly,relative standard deviations are 2.4 ％～7.0 ％ and 1.8 ％～9.4 ％.The minimium detection limit is 0.002 6 μg/L,lower than LOD (0.06 μg/L) in Chinese drinking water standards.