Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de La Laguna (ULL), La Laguna (Tenerife), Spain.
J Sep Sci. 2013 Feb;36(3):556-63. doi: 10.1002/jssc.201200782. Epub 2013 Jan 10.
In this manuscript, a dispersive SPE method based on the use of multiwalled carbon nanotubes has been developed for the determination of 15 organophosphorus pesticides residues including some of their metabolites (disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, disulfoton sulfone, and fensulfothion) from real environmental waters (run-off, mineral and tap water) by GC with nitrogen phosphorus detection. Factors that affect the enrichment efficiency such as sample volume, multiwalled carbon nanotubes amount, and volume of eluent were studied. The optimized method was validated in terms of matrix-matched calibration, recovery, precision, and accuracy for the three analyzed samples. In this last case, the developed Student's t test demonstrated that there were no significant differences between real and spiked concentrations. Optimum dispersive SPE conditions (extraction of 200 mL of water, pH 6.0, with 130 mg of multiwalled carbon nanotubes, elution with 25 mL of dichloromethane for run-off and tap water and 30 mL for mineral water) allowed the quantitative extraction of analytes at levels lower than the maximum residues limits legislated by the European Union, with LODs between 1.16 and 93.6 ng/L. Absolute recovery values achieved were in the range of 67-107% (RSD values <10.1%).
在本手稿中，开发了一种基于使用多壁碳纳米管的分散固相萃取方法，用于测定包括一些代谢物（二硫代磷酸砜、乙草胺、卡苏福斯、二甲氧基、特福松、二硫代磷酸、甲基毒死蜱、马拉氧肟、硫丹、吡虫啉甲基、马拉硫磷、毒死蜱、特福松砜、二硫代磷酸砜和福斯硫磷）在内的 15 种有机磷农药残留，这些农药残留来自真实环境水样（径流、矿泉水和自来水），采用气相色谱法（GC）结合氮磷检测。研究了影响富集效率的因素，如样品体积、多壁碳纳米管用量和洗脱液体积。对三种分析样品进行了基质匹配校准、回收率、精密度和准确度的优化方法验证。在最后一种情况下，开发的学生 t 检验证明真实浓度和加标浓度之间没有显著差异。最佳分散固相萃取条件（萃取 200 毫升水，pH 值 6.0，用 130 毫克多壁碳纳米管，用 25 毫升二氯甲烷洗脱径流和自来水，用 30 毫升矿泉水）允许在低于欧盟规定的最大残留限量的水平下定量提取分析物，检出限在 1.16 和 93.6 ng/L 之间。获得的绝对回收率值在 67-107%（RSD 值<10.1%）范围内。
