Pintado-Herrera Marina G, González-Mazo Eduardo, Lara-Martín Pablo A
Physical Chemistry Department, Faculty of Marine and Environmental Sciences, University of Cadiz, Campus de Excelencia Internacional del Mar (CEIMAR), Cadiz 11510, Spain.
Physical Chemistry Department, Faculty of Marine and Environmental Sciences, University of Cadiz, Campus de Excelencia Internacional del Mar (CEIMAR), Cadiz 11510, Spain.
Anal Chim Acta. 2014 Dec 3;851:1-13. doi: 10.1016/j.aca.2014.05.030. Epub 2014 May 22.
This work presents the development, optimization and validation of a multi-residue method for the simultaneous determination of 102 contaminants, including fragrances, UV filters, repellents, endocrine disruptors, biocides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and several types of pesticides in aqueous matrices. Water samples were processed using stir bar sorptive extraction (SBSE) after the optimization of several parameters: agitation time, ionic strength, presence of organic modifiers, pH, and volume of the derivatizing agent. Target compounds were extracted from the bars by liquid desorption (LD). Separation, identification and quantification of analytes were carried out by gas chromatography (GC) coupled to time-of-flight (ToF-MS) mass spectrometry. A new ionization source, atmospheric pressure gas chromatography (APGC), was tested. The optimized protocol showed acceptable recovery percentages (50-100%) and limits of detection below 1ngL(-1) for most of the compounds. Occurrence of 21 out of 102 analytes was confirmed in several environmental aquatic matrices, including seawater, sewage effluent, river water and groundwater. Non-target compounds such as organophosphorus flame retardants were also identified in real samples by accurate mass measurement of their molecular ions using GC-APGC-ToF-MS. To the best of our knowledge, this is the first time that this technique has been applied for the analysis of contaminants in aquatic systems. By employing lower energy than the more widely used electron impact ionization (EI), AGPC provides significant advantages over EI for those substances very susceptible to high fragmentation (e.g., fragrances, pyrethroids).
本研究介绍了一种多残留方法的开发、优化及验证，该方法可同时测定水性基质中的102种污染物，包括香料、紫外线过滤剂、驱虫剂、内分泌干扰物、杀生剂、多环芳烃（PAHs）、多氯联苯（PCBs）以及几种农药。在对搅拌时间、离子强度、有机改性剂的存在、pH值和衍生剂体积等多个参数进行优化后，采用搅拌棒吸附萃取（SBSE）对水样进行处理。通过液体解吸（LD）从搅拌棒中萃取目标化合物。采用气相色谱（GC）与飞行时间（ToF-MS）质谱联用进行分析物的分离、鉴定和定量。测试了一种新型电离源——大气压气相色谱（APGC）。优化后的方法对大多数化合物显示出可接受的回收率（50-100%），检测限低于1ngL(-1)。在包括海水、污水、河水和地下水在内的几种环境水生基质中，确认了102种分析物中的21种的存在。通过使用GC-APGC-ToF-MS对其分子离子进行精确质量测量，还在实际样品中鉴定出了非目标化合物，如有机磷阻燃剂。据我们所知，这是该技术首次应用于水生系统中污染物的分析。与更广泛使用的电子轰击电离（EI）相比，APGC采用的能量较低，对于那些极易发生高碎片化的物质（如香料、拟除虫菊酯），APGC比EI具有显著优势。
