蔬菜中苯甲酰脲类药物残留的测定方法研究

Multiresidue Determination of Benzoylurea Insecticides in Vegetable Matrices

建立了一步有机溶剂提取、HPLC分离、紫外检测器检测7种苯甲酰脲类药物（除虫脲、灭幼脲、杀铃脲、氟铃脲、氟苯脲、氟虫脲和氟啶脲）在蔬菜中残留量的方法.考察了不同提取溶剂（乙酸乙酯和乙腈）的提取效率;研究了不同C18固相萃取小柱、活性碳、自制弗罗里硅土柱和GPC对蔬菜样品的净化效果;实验了不同的梯度淋洗程序分离7种药物.通过对黄瓜、大白菜、西红柿和包心菜4种蔬菜的4种添加水平和4次重复性实验,建立了一种以乙腈为提取溶剂和以弗罗里硅土柱为净化柱的高效液相色谱法测定7种苯甲酰脲类药物.该方法线性范围为：0.02～1.5 mg/L,7种苯甲酰脲类药物的相关系数均大于0.999,其检出限为0.02～0.05 mg/kg（S/N=10）;在0.05～1.0 mg/kg之间的添加回收率为80 %～120%;相对标准偏差小于15%.方法完全符合残留分析的要求.

One-step extraction and high performance liquid chromatography （HPLC） with ultraviolet detection have been developed and validated for the determination of seven kinds of benzoylurea insecticides （diflubenzuron, chlorbenzuron, triflumuron, hexaflumuron, teflubenzuron, flufenoxuron and chlorfluazuron） residues in vegetable matrices including Chinese cabbage, tomato, cabbage and cucumber. The extraction efficiency of ethyl acetate and acetonitrile,different cleanup methods including C18 solid phase extraction （SPE） cartridge, hydrophilic-lipophilic balance （HLB） SPE cartridge, activated carbon, florisil and Vario GPC and separation by HPLC are extensively investigated. The extraction recoveries of the seven kinds of benzoylurea insecticides are between 80% and 120% for spiked level of 0.05 - 1.0 mg/kg. The limits of quantification are ranged from 0. 02 to 0.05 mg/kg for the seven pesticides （ S/N = 10）. There are good linear correlations between the peak areas and concentrations of the seven kinds of benzoylurea insecticides, the line ar range is 0.02 - 1.5 mg/L and the correlation coefficients are above 0. 999.