加速溶剂萃取-在线衍生-气相色谱-质谱法同时分析土壤中有机氯农药和酸性除草剂  

Simultaneous Determination of Organochlorine Pesticides and Acid Herbicides in Soil by In situ Derivatization Method with Accelerated Solvent Ectraction

作　　者：桂建业[1] 魏福祥[2] 齐继祥[1] 陈宗宇[1] 张兆吉[1] 张莉[1] 张永涛[1] 李晓亚[1] 左海英[1] 王浩然[2] 

机构地区：[1]中国地质科学院水文地质环境地质研究所,正定050803 [2]河北科技大学,石家庄050018

出　　处：《分析化学》2011年第12期1877-1881,共5页Chinese Journal of Analytical Chemistry

基　　金：中国地质科学院基本科研业务费(No.Q201017;SK201008);地质调查工作项目(No.1212011120274)资助

摘　　要：建立了土壤中13种极性除草剂与20种非极性有机氯农药的同时萃取检测的方法。利用加速溶剂萃取过程中的温度环境与溶剂环境,使强极性氯代酸性除草剂与五氟苄基溴在萃取池内反应,酯化产物的极性显著降低。利用丙酮溶剂使之与非极性的有机氯农药同时萃取;利用衍生产物与有机氯农药的高电负性使除草剂与有机氯农药在气相色谱负化学源质谱上同时检测;开发了络合剂Na4 EDTA,并通过温度条件实验使整个萃取和衍生时间缩短。10.0 g土壤样品、1.5 mL蒸馏水、0.50 g Na4-EDTA充分混合,加入过量衍生试剂,采用加速溶剂萃取仪,样品在100℃,10.3 MPa压力下,10 min完成衍生及萃取过程,萃取液脱水并净化后进行负化学质谱检测。本方法灵敏度高,所有组分检出限均在10.0μg/kg以下,回收率为68%～120%,精密度为2.8%～7.9%。A simultaneous extraction and sensitive determination method of 13 polar herbicide and 20 nonpolar organochlorine pesticides was established.Reaction of esterification between herbicides and Alpha-bromo-pentafluorotoluene（PFBBr） was carried through in the cell of accelerated solvent extraction（ASE）,the esterification products of herbicide and organochlorine pesticides were extracted with the proper temperature and extraction solvent.Take the advantage of similar electronegativity of esterification products and the organochlorine pesticides,two types of organic compounds were detected simultaneously.The total extraction and esterification time was shortened through optimizing temperature and the addition of complexing agent.For the mixture of 10.0 g soil,1.5 mL H2O,and 0.5 g Na4-EDTA,under the conditions of elevated temperature of 100 ℃,pressure of 10.3 MPa,the derivatization and extraction was completed in 10 min by accelerated solvent extractor with excessive PFBBr in the extraction cell.The extract was detected by gas chromatography-negative chemical ionization-mass spectrometry after drying and clean-up.The method is very sensitive with detection limit of all compounds below 10.0 μg/kg.The recovery was 68%-120% and the RSD is between 2.8% and 7.9%.

关 键 词：在线衍生 土壤 除草剂 有机氯 气相色谱 负化学源质谱 

分 类 号：O657.63[理学—分析化学] X833[理学—化学]