菠菜中3种新烟碱杀虫剂多残留分析方法研究

摘要

This study established the acetonitrile as dispersion solvent,with DWCNTs-COOH and GCB as disper-sion matrix material in dinotefuran,nitenpyram and imidacloprid residue matrix dispersion extraction pretreat-ment for spinach samples,set up and optimized HPLC of the acetonitrile gradient elution residual sample with quantitative method of external standard.The results showed that the optimal retention time for dinotefuran, nitenpyram and imidacloprid were 6.8,8.6 and 17.7 min,respectively.They had a good linear relationship with the corresponding chromatographic peak area ranging from 0.025 to 25.00 mg/L in mass concentration.The av-erage recovery of dinotefuran,nitenpyram and imidacloprid was more than 75%;the level of relative standard de-viation was less than 10% in spinach.The minimum detectable concentration were 0.091 2 mg/L (dinotefuran), 0.080 8 mg/L (nitenpyram)and 0.062 8 mg/L (imidacloprid)under the conditions of chromatographic method. The results indicated that the residue sample pretreatment methods and sample analysis methods were simple,effi-cient,economical and reliable,and could meet the requirements for quantitative detection of the three kinds of pesticide residues in spinach.%研究确立了以乙腈为分散萃取溶剂，以羧基化双壁碳纳米管（DWCNTs-COOH）和石墨化碳黑（GCB）为基质分散材料的菠菜样品中呋虫胺、烯啶虫胺和吡虫啉残留的基质分散萃取前处理方法，建立并优化了乙腈梯度洗脱的高效液相色谱（HPLC）残留样品外标定量方法。结果表明，优化色谱条件下，呋虫胺、烯啶虫胺和吡虫啉色谱保留时间分别为6．8、8．6和17．7 min，在0．025～25．00 mg／L 范围内与对应色谱峰面积具有良好的线性关系。呋虫胺、烯啶虫胺和吡虫啉在菠菜中3个添加水平的回收率均在75％以上，相对标准偏差均小于10％，该色谱条件下方法的最低检测浓度分别为0．0912 mg／L（呋虫胺）、0．0808 mg／L（烯啶虫胺）和0．0628 mg／L（吡虫啉），表明研究建立的残留样本前处理方法和样品检测方法简便、高效、经济、可靠，可满足3种农药在菠菜中残留的定量检测要求。