Juhler R K
Institute of Food Research and Nutrition, Danish Veterinary and Food Administration, Søborg, Denmark.
Analyst. 1998 Jul;123(7):1551-6. doi: 10.1039/a802323i.
A method for quantification of pesticide residues in meat and fatty matrices was developed using supercritical fluid extraction (SFE). The SFE method allows selective extraction of residues and subsequent gas chromatography analysis without further clean-up. Quantification was done by GC using nitrogen-phosphorus detection and electron capture detection. Initial method development was made using organophosphorus pesticides (OPPs). The dependence of fat and OPP residue recovery on supercritical fluid density, temperature, flow rate and extraction time was investigated through a reduced factorial design. Since temperature and density were found to have pronounced effect on the recovery of OPPs these extraction parameters were studied using a new arbitrary measure for co-extractivity. An optimisation score was established as relative pesticide recovery subtracted by relative fat recovery. Using this algorithm a response plane was modelled varying the primary factors temperature and density. The applicability of this approach and the algorithm was verified. The polarity range covered by the SFE method was demonstrated using OPPs: chlorpyrifos, chlorpyrifos-methyl, malathion, pirimifos-methyl and prothiofos. Additionally the final method was evaluated using four pesticides that are not OPPs: carbofuran, phorate, procymidone and vinclozolin. All pesticides showed good recovery (78-95%), and limits of detection (0.01-0.03 mg kg-1) and limits of determination (0.01-0.05 mg kg-1) meet the requirements set by the European Council (Directive 96/33/EEC). Compared to traditional methods based on organic solvent extraction, the SFE method is fast, less labour intensive, uses smaller amounts of potentially harmful solvents and has the potential to be fully automated.
开发了一种使用超临界流体萃取（SFE）定量测定肉类和脂肪基质中农药残留的方法。该SFE方法允许选择性萃取残留，随后进行气相色谱分析而无需进一步净化。通过使用氮磷检测和电子捕获检测的气相色谱法进行定量。最初的方法开发使用有机磷农药（OPPs）。通过简化析因设计研究了脂肪和OPPs残留回收率对超临界流体密度、温度、流速和萃取时间的依赖性。由于发现温度和密度对OPPs的回收率有显著影响，因此使用一种新的共萃取性任意度量方法来研究这些萃取参数。建立了一个优化分数，即相对农药回收率减去相对脂肪回收率。使用该算法对主要因素温度和密度变化的响应面进行建模。验证了该方法和算法的适用性。使用OPPs（毒死蜱、甲基毒死蜱、马拉硫磷、甲基嘧啶磷和丙硫磷）证明了SFE方法覆盖的极性范围。此外，使用四种非OPPs农药（克百威、甲拌磷、腐霉利和乙烯菌核利）对最终方法进行了评估。所有农药均显示出良好的回收率（78-95%），检测限（0.01-0.03 mg kg-1）和定量限（0.01-0.05 mg kg-1）符合欧洲理事会规定的要求（96/33/EEC指令）。与基于有机溶剂萃取的传统方法相比，SFE方法快速、劳动强度低、使用的潜在有害溶剂量少且具有完全自动化的潜力。
