蔬菜、水果中吡虫啉的测定

Determination of Imidacloprid in Vegetables and Fruits

目的:对《水果、蔬菜及茶叶中吡虫啉残留的测定高效液相色谱法》(GB/T 23379—2009)进行改进。方法:用纯水替代0.1%的磷酸溶液作流动相,对方法的标准曲线、精密度、准确度、检出限进行验证。结果:改进后的方法检出限为0.05 mg·kg^(-1),在0.05~0.40μg·mL^(-1)、0.40~0.80μg·mL^(-1),吡虫啉峰面积与浓度的线性方程分别为y=60.6100x+0.4909(r=0.9993)、y=61.5511x+0.7815(r=0.9934),线性关系良好,相对标准偏差为2.9%,样品加标回收率为96.5%~103.0%。结论:该方法使用纯水作流动相可以减少对色谱柱的损害,延长色谱柱使用寿命,缩短试验后冲洗色谱柱时间,使实验更环保高效;同时具有操作简单的特点,适用于蔬菜、水果中吡虫啉的测定。

Objective:To improve the method in GB/T 23379-2009.Method:0.1%phosphoric acid solution was replaced by pure water as the mobile phase,and the standard curve,precision,accuracy and detection limit of the method were verified.Result:The detection limit of the improved method was 0.05 mg·kg^(-1).When the linear ranges were 0.05~0.40μg·mL^(-1) and 0.40~0.80μg·mL^(-1),the linear equations of imidacloprid peak area versus concentration were y=60.6100x+0.4909(r=0.9993),y=61.5511x+0.7815(r=0.9934),respectively,with good linearity,relative standard deviation of 2.9%and sample spiked recoveries of 96.5%~103.0%.Conclusion:The method can reduce the damage to the column by using pure water as the mobile phase,prolong the service life of the column,shorten the time of rinsing the column after the test,and make the experiment more environmentally friendly and efficient;meanwhile,it has the characteristics of simple operation and is suitable for the determination of imidacloprid in vegetables and fruits.