Center of Evidence Identification, Chongqing Public Security Bureau, Chongqing 400021, China.
Center of Evidence Identification, Chongqing Public Security Bureau, Chongqing 400021, China.
J Chromatogr B Analyt Technol Biomed Life Sci. 2014 Mar 1;951-952:89-95. doi: 10.1016/j.jchromb.2014.01.027. Epub 2014 Jan 28.
A method was developed for determination of amitraz and its metabolites, N-[2,4-(dimethylphenyl)-N'-methylformamidine (DMPF), 2,4-dimethylformamidine (DMF), 2,4-dimethylaniline (DMA) in whole blood. The analytes were extracted by solid-phase extraction (SPE) using dichloromethane, acetonitrile and methanol (2:1:1) mixture as elute solution. Analysis was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the positive ion mode using multiple reaction monitoring (MRM) technique. Collision-induced dissociation (CID) of amitraz at the electrospray source in MS/MS was observed in the analytic conditions. The method was validated in human whole blood spiked at three concentration levels. The low limit of detection (LOD) and the low limit of quantification (LOQ) for all the analytes were below 0.5μg/L and 2μg/L, respectively. Recoveries were between 90.2% and 104.5%, Bias and relative standard deviation (RSD) were below 15% (n=6). The good linear relationships were obtained in certain concentration ranges of amitraz and its metabolites. The results demonstrated the method is exclusive, sensitive and accurate, and can be applied in forensic toxicology.
建立了一种同时测定全血中双甲脒及其代谢物 N-[2,4-（二甲基苯基）-N'-甲基甲脒]（DMPF）、2,4-二甲基甲脒（DMF）、2,4-二甲基苯胺（DMA）的方法。采用二氯甲烷-乙腈-甲醇（2:1:1）混合溶液作为洗脱液，通过固相萃取（SPE）进行提取。采用液相色谱-串联质谱法（LC-MS/MS），正离子模式，多反应监测（MRM）技术进行分析。在 MS/MS 中，于电喷雾源下观察到双甲脒的碰撞诱导解离（CID）。在三种浓度水平下对全血进行加标验证，所有分析物的检测限（LOD）和定量限（LOQ）均低于 0.5μg/L 和 2μg/L。回收率在 90.2%~104.5%之间，偏差和相对标准偏差（RSD）均低于 15%（n=6）。在一定浓度范围内，双甲脒及其代谢物均具有良好的线性关系。结果表明，该方法专属性强、灵敏度高、准确度好，可应用于法医毒物学。
