气相色谱法快速测定豆角中4种有机氯农药残留
2016-10-20杨娟吴星祥黎小鹏陈楠马世柱冯敏铃
杨娟 吴星祥 黎小鹏 陈楠 马世柱 冯敏铃

摘要 研究了豆角中的4种有机氯农药(包括林丹、氟虫腈、p,p′-DDT、o,p′-DDT)残留量的气相色谱测定方法。样品经乙腈提取,弗罗里矽柱柱净化,HP-5毛细管柱分离,ECD检测器检测,基质匹配外标法定量。4种有机氯农药在0.05~1.00 mg/L浓度范围内均有良好的线性关系,相关系数不低于0.999 42,在13 min内获得良好的分离,4种有机氯农药加标回收率为86.4%~108.7%,相对标准偏差在(n=6)4.9%~10.5%之间。该方法适于豆角中4种有机磷农残的快速检测。
关键词 气相色谱法;测定;豆角;有机氯农药;残留量
中图分类号 X839.2;O657.71 文献标识码 A 文章编号 1007-5739(2016)05-0143-02
Abstract A gas chromatography method was developed for rapid determination of 4 organochlorine pesticides residue(including γ-BHC、fipronil、p,p′-DDT、o,p′-DDT)in Vigna unguiculata.The samples were extracted with acetonitrile and cleaned up by solid-phase florisil column,then separated in a HP-5 capillary column and detected with ECD detector.A matrix matched external standard was used for quantitative analysis.Four organochlorine pesticides well separated within 13 min.The calibration curves were in good linearity between the peak area and the concentration of 0.05~1.00 mg/L for 4 organochlorine pesticides with correlation coefficients not less than 0.999 42.The spiked recoveries ranged from 86.4% to 108.7% with RSD′s(n=6)in the range of 4.9%~10.5%.The proposed method was suitable for fast detecting 4 organochlorine pesticide in Vigna unguiculata.
Key words gas chromatography;determination;Vigna unguiculata;organochlorine pesticide;residue
豆角,又叫作豇豆,别名长角豆、带豆、裙带豆,属豇豆种中能形成长形豆荚的栽培种,一年生缠绕草本植物。含有各种维生素和礦物质等。嫩豆荚肉质肥厚,炒食脆嫩,也可烫后凉拌或腌泡。豆角营养成分很好,是蔬菜中的肉类。
由于豆角的病虫害较多,用药频繁,农药的合理使用可起到保产增收的作用,但农药的不合理使用和过度使用又会间接危害人类健康[1-2]。目前,有关豆角中多农药残留检测鲜有报道[3]。笔者采用气相色谱法同时对豆角中林丹、氟虫腈、p,p′-DDT、o,p′-DDT等4种有机氯农药进行测定,该方法前处理简单,回收率和精密度均较好。
1 材料与方法
1.1 仪器与试剂
T-18 digital均质机(德国IKA公司),百分之一电子天平(Precisa公司),Agilent 6890N型气相色谱仪(配ECD检测器,美国安捷伦公司),XW-80A旋涡混合器(其林贝尔公司),ASPEC XL4全自动固相萃取仪(法国吉尔森公司),HGC-36A氮吹仪(天津恒奥公司)。
色谱纯丙酮和色谱纯正己烷(均由德国Merck公司生产);……
