Zacharis Constantinos K, Rotsias Ilias, Zachariadis Petros G, Zotos Anastasios
Research Laboratory for the Physical and Chemical Testing of Foods, Department of Food Technology, School of Food Technology and Nutrition, Alexander Technological Educational Institute (ATEI) of Thessaloniki, 57400 Thessaloniki, Greece; Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Research Laboratory for the Physical and Chemical Testing of Foods, Department of Food Technology, School of Food Technology and Nutrition, Alexander Technological Educational Institute (ATEI) of Thessaloniki, 57400 Thessaloniki, Greece.
Food Chem. 2012 Oct 1;134(3):1665-72. doi: 10.1016/j.foodchem.2012.03.073. Epub 2012 Mar 28.
A simple dispersive liquid-liquid microextraction (DLLME) protocol for the determination of 15 organochlorine pesticides residues in honey is proposed. The selected pesticides were separated using gas chromatography and detected by electron capture (ECD) or ion trap mass spectrometry (GC-IT/MS). Several parameters affecting the extraction efficiency namely type and volume of organic extraction solvent, type and volume of disperser solvent, sample pH, ionic strength, extraction time and centrifugation speed were systematically investigated. The final DLLME protocol involved the addition of 750 μL acetonitrile (disperser) and 50 μL chloroform (extraction solvent) into a 5 mL aqueous honey solution followed by centrifugation. The sedimented organic phase (chloroform) were analysed directly by GC-IT/MS or evaporated and reconstituted in acetonitrile prior to the GC-ECD analysis. The analytical performance of the GC-ECD and GC-IT/MS methods was compared and discussed. Under the selected experimental conditions, the enrichment factors varied between of 36 and 114. The limits of detection (LOD) were in the range of 0.02-0.15 μg L(-1) (0.4-3 ng g(-1)) for GC-ECD and 0.01-0.2 μg L(-1) (0.2-4 ng g(-1)) for GC-IT/MS which is adequate to verify compliance of products to legal tolerances. The proposed method was applied to the analysis of the selected organochlorine pesticides residues in various honey samples obtained from Greek region. Mean recoveries were ranged from 75% to 119% while the precision was better than 20% in both methodologies.
本文提出了一种简单的分散液液微萃取（DLLME）方法，用于测定蜂蜜中15种有机氯农药残留。选用的农药通过气相色谱分离，并用电子捕获（ECD）或离子阱质谱（GC-IT/MS）进行检测。系统研究了影响萃取效率的几个参数，即有机萃取溶剂的类型和体积、分散剂溶剂的类型和体积、样品pH值、离子强度、萃取时间和离心速度。最终的DLLME方法是向5 mL蜂蜜水溶液中加入750 μL乙腈（分散剂）和50 μL氯仿（萃取溶剂），然后进行离心。沉淀的有机相（氯仿）直接用GC-IT/MS分析，或在GC-ECD分析前蒸发并重新溶解于乙腈中。比较并讨论了GC-ECD和GC-IT/MS方法的分析性能。在选定的实验条件下，富集因子在36至114之间变化。GC-ECD的检测限（LOD）在0.02-0.15 μg L(-1)（0.4-3 ng g(-1)）范围内，GC-IT/MS的检测限在0.01-0.2 μg L(-1)（0.2-4 ng g(-1)）范围内，足以验证产品是否符合法定公差。该方法应用于分析从希腊地区采集的各种蜂蜜样品中选定的有机氯农药残留。两种方法的平均回收率在75%至119%之间，精密度均优于20%。
