月桂酸胶束电动毛细管色谱快速测定氨基甲酸脂类农药的研究

Rapid Determination of N-methylcarbamate Pesticides by Micellar Electrokinetic Capillary Chromatography Using Lauric Acid Buffer System

以月桂酸表面活性剂和氨水组成缓冲溶液,建立了毛细管胶束电动色谱快速测定七种氨基甲酸脂类农药的方法。对电泳介质的种类及浓度、pH值、操作电压和进样时间等影响因素进行了优化,以45 mmol/L月桂酸(乙醇溶)和120 mmol/L氨水(用0.1 mol/L NaOH调至pH=9.5)为电泳介质,在4.5 min内实现对速灭威、残杀威、克百威、抗蚜威、异丙威、硫双威、双氧威的分离检测。结合固相萃取(SPE)对农田水样进行测定,各农药检出限为2.0～15μg/L,回收率为85%～107%,相对标准偏差为4.3%～8.3%。

A micellar electrokinetic capillary chromatographic method for fast determination of N-methylcarbamate pesticides was developed by using lauric acid buffer system.The effect of some key factors,such as concentration of lauric acid and ammonia,addition of organic solvent,capillary temperature and applied voltage on the separation was investigated.Under the optimized conditions,45 mmol/L lauric acid（dissolve in ethanol） and 120 mmol/L ammonia（pH=9.5） as the running buffer,the baseline separation of seven N-methylcarbamate pesticides was achieved within 4.5 mins.The detection limit of each analytes varied from 2.0 to 15 μg/L with the preconcentration of ODS-C18 solid phase extraction column.The average recoveries of each analytes from farm water ranged from 85% to 107% for all with RSDs below 8.3%（n=5）.