Yuan Ning, Yu Binbin, Zhang Maosheng, Zeng Jingbin, Chen Xi
Key Laboratory of Analytical Sciences, Ministry of Education, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
Se Pu. 2006 Nov;24(6):636-40.
The issue of residues including organochlorine and pyrethroid pesticides in tea has made a great attention of researchers and customers in the world. Although some analytical methods have well been established to detect these pesticides, the sample preparations are generally laborious, time-consuming, and some of the procedures caused environmental pollution. Solid phase microextraction (SPME) is a novel sample preparation technique since it is of simplicity, high efficiency and solvent free. SPME was firstly developed to address the need to facilitate environment monitoring. In recent years, great efforts have been made in the analysis of pesticide residues in agricultural products by SPME. In this research, a microwave assisted extraction solid phase microextraction-gas chromatography (MAE-SPME-GC) was applied for the simultaneous determination of organochlorine and pyrethroid pesticides, such as benzene hexa chlorides (alpha-BHC, beta-BHC, gamma-BHC and delta-BHC), 1-(2-chlorophenyl)-1-(4-chlorophenyl)-2, 2, 2-trichloroethane (o, p'-DDT), 2, 2-bis (4-chlorophenyl)-1, 1-dichloroethylene (DDE), 2, 2-bis (4-chlorophenyl)-1, 1-dichloroethane (DDD), 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1, 1, 1-trichloroethane (p, p'-DDT), cypermethrin and fenvalerate. All the tested pesticides were baseline separated under the experimental conditions, except for DDD and o, p'-DDT. The concentration of each pesticide was calibrated by external standard method. The linearities were found to be in the correlation coefficient range of 0.970 5 to 0.998 4 for the tested pesticides between the mass concentrations and peak areas, except for fenvalerate. The recoveries, relative standard deviations and detection limits for the 10 pesticides were 64% - 121%, 10.4% -22.9%, and 1 - 50 ng/L, respectively. The proposed method was successfully applied to the determination of organochlorine pesticide residues in three kinds of teas from the local market. The experimental results demonstrated that MAE-SPME-GC was a fast, sensitive and green technique for the analysis of trace quantity of pesticides in solid substrate foods.
茶叶中有机氯和拟除虫菊酯类农药等残留问题已引起全球研究人员和消费者的高度关注。尽管已建立了一些检测这些农药的分析方法，但样品制备通常费力、耗时，且有些步骤还会造成环境污染。固相微萃取（SPME）是一种新型的样品制备技术，具有操作简单、高效且无需使用溶剂的特点。SPME最初是为满足环境监测的需求而开发的。近年来，在利用SPME分析农产品中农药残留方面已做出了巨大努力。在本研究中，采用微波辅助萃取固相微萃取 - 气相色谱法（MAE - SPME - GC）同时测定有机氯和拟除虫菊酯类农药，如六六六（α - BHC、β - BHC、γ - BHC和δ - BHC）、1 - （2 - 氯苯基） - 1 - （4 - 氯苯基） - 2,2,2 - 三氯乙烷（o,p' - DDT）、2,2 - 双（4 - 氯苯基） - 1,1 - 二氯乙烯（DDE）、2,2 - 双（4 - 氯苯基） - 1,1 - 二氯乙烷（DDD）、2 - （2 - 氯苯基） - 2 - （4 - 氯苯基） - 1,1,1 - 三氯乙烷（p,p' - DDT）、氯氰菊酯和氰戊菊酯。在实验条件下，除DDD和o,p' - DDT外，所有被测农药均实现了基线分离。每种农药的浓度通过外标法进行校准。除氰戊菊酯外，被测农药的质量浓度与峰面积之间的线性关系良好，相关系数范围为0.970 5至0.998 4。10种农药的回收率、相对标准偏差和检测限分别为64% - 121%、10.4% - 22.9%和1 - 50 ng/L。所提出的方法成功应用于测定当地市场上三种茶叶中的有机氯农药残留。实验结果表明，MAE - SPME - GC是一种快速、灵敏且绿色的技术，可用于分析固体基质食品中的痕量农药。
