顶空溶剂吸收—气相色谱法对莴笋中代森锌残留量的测定
2018-06-07陈翔王晓菁葛谦张锋锋
陈翔 王晓菁 葛谦 张锋锋



摘要:采用顶空溶剂吸收-气相色谱法(配电子捕获检测器),以盐酸·氯化亚锡(Cl·SnCl2)为反应试剂,正己烷为吸收溶剂,以反应最终生成的二硫化碳测定值代表代森锌含量,建立莴笋中代森锌检测方法。分析莴笋不同部位代森锌的残留,探明其残留分布情况及消解规律。结果表明,该方法操作简便,色谱分析时间短,线性良好,检出限为0.10 mg/kg,代森锌平均转化率为90.4%~98.0%,平均回收率为82.8%~103.6%,相对标准偏差为2.4%~6.3%;莴笋中代森锌残留量表现为莴笋叶>带皮莴笋茎>去皮莴笋茎,施药14 d后,代森锌降解率均达到85%以上。
关键词:代森锌;顶空溶剂吸收;气相色谱;莴笋;残留
中图分类号:O657.7+1 文献标识码:A 文章编号:0439-8114(2018)07-0114-03
DOI:10.14088/j.cnki.issn0439-8114.2018.07.027
Determination of Zineb Residue in Asparagus Lettuce by Headspace Solvent Absorption-Gas Chromatography
CHEN Xiang,WANG Xiao-jing,GE Qian,ZHANG Feng-feng
(Quality Standards and Testing Institute of Agricultural Technology,Yinchuan 750002,China)
Abstract: The reaction was carried out using a headspace-absorption GC-ECD,HCl·SnCl2 as the reaction reagent,n-hexane as the sorption solvent,determine the residue of zineb indicated by CS2,establish a method for the detection of zineb in asparagus lettuce. Analysis the residues in different parts of lettuceand to determine its residual distribution and its digestion. This method is simple,fast and has good linearity,the detectable limit is 0.10 mg/kg,the average conversion rate of zineb was 90.4%~98.0%,the average recovery was 82.8%~103.6%,relative standard deviation was 2.4%~6.3%. The residue of zineb in asparagus lettuce showed that leaves>stems>peeled stems,14 days after spraying,zineb digestion rate reached more than 85%.
Key words: Zineb; Headspace-solvent absorption; gas chromatography; asparagus lettuce; residue
代森锌(Zineb)是一种二硫代氨基甲酸盐类农药,目前市售主要产品为80%代森锌可湿性粉剂,是一种农业生产中常见的杀菌剂,广泛用于防治各种真菌引起的番茄早疫病、芦笋茎枯病、马铃薯晚疫病、花生叶斑病等常见病害[1-5]。尽管代森锌属低毒农药,但有研究表明,代森锌及其代谢物乙撑硫脲(ETU)残留量较高时有较大几率致畸、致突变,甚至致癌[6,7]。目前其主要检测方法有分光光度法、液相色谱-质谱联用法、气相色谱法等[8-10],与其他检测方法相比,气相色谱方法对样品的处理简便、快速,且准确度与精密度均能够满足要求,研究在现有文献基础上,结合标准SN/T 0157-1992进行改进,采用溶剂吸收处理,经GS-GASPRO色谱柱分离并使用气相色谱配ECD检测器测定莴笋中代森锌含量,取得了理想成效。……p>
