Department of Analytical Chemistry, Nutrition and Food Science, IIAA - Institute for Food Analysis and Research, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
J Chromatogr A. 2013 Jul 26;1300:85-94. doi: 10.1016/j.chroma.2013.05.064. Epub 2013 Jun 3.
This study presents the development and validation of a new analytical method for the simultaneous determination of fifteen analytes classified as halogenated flame retardants (HFRs) - nine brominated diphenyl ethers (BDEs) and six novel HFRs - in different kinds of mollusks using matrix solid-phase dispersion (MSPD) followed by gas chromatography coupled to negative chemical ionization-mass spectrometry (GC-NCI-MS). The proposed method is the first one developed for such a broad range of HFRs in aquatic biota, featuring several advantages, including low solvent and sample intake, simplicity of operation, reduced cost and integration of extraction and clean-up into a single step. Under optimal conditions, 0.5g of freeze-dried sample, 0.5g of a primary-secondary amine (PSA) as solid support, a sorbent combination of 1.75g of florisil (deactivated with 5% Milli-Q water), 1.75g of acidified silica (10% (w/w) H2SO4) and 0.5g of silica, and 10mL dichloromethane as elution solvent were used. Standard addition over the extract was required however for the correct quantification due to matrix effects in the GC system, particularly for novel HFRs, that could not be compensated with the internal standards. The method afforded LODs in the range of 0.003-0.07ngg(-1) dry weight (0.0006-0.014ngg(-1) on a wet weight basis, assuming an 80% sample water content), except for decabromodiphenyl ethane (DBDPE) (0.6ngg(-1) dry weight, 0.12ngg(-1) wet weight). The accuracy of the method was evaluated with three different types of spiked mollusk species using surrogate standards and standard addition over the extract for quantification and the recoveries were in the 70-120% range, except for bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (DEHTBP) in clam (Ruditapes philippinarum) samples (46% recovery). Moreover, the method was successfully validated with standard reference materials (SRMs) of salmon and mussel tissues for BDEs. Finally, the method was applied to the determination of HFRs in different kind of freeze-dried mollusks: mussel (Mytilus galloprovincialis), cockle (Cerastoderma edule) and clam (R. philippinarum). Raft cultured mussels showed the highest concentrations of HFRs (up to 0.8ngg(-1) wet weight of BDE-209).
本研究提出了一种新的分析方法，用于使用基质固相分散（MSPD）结合气相色谱-负化学电离-质谱（GC-NCI-MS）同时测定十五种分类为卤代阻燃剂（HFRs）的分析物-九溴二苯醚（BDEs）和六种新型 HFRs-在不同种类的软体动物中。所提出的方法是第一个针对水生生物中如此广泛的 HFR 开发的方法，具有许多优点，包括低溶剂和样品摄入量、操作简单、成本降低以及提取和净化集成到一个步骤中。在最佳条件下，使用 0.5g 冷冻干燥样品、0.5g 一级-二级胺（PSA）作为固体支撑、1.75g 弗罗里硅土（用 5%Milli-Q 水失活）、1.75g 酸化硅胶（10%（w/w）H2SO4）和 0.5g 硅胶，以及 10mL 二氯甲烷作为洗脱溶剂。由于 GC 系统中的基质效应，特别是对于新型 HFRs，需要对提取物进行标准添加才能进行正确定量，这些基质效应无法通过内标补偿。该方法提供的检测限范围为 0.003-0.07ngg(-1)干重（0.0006-0.014ngg(-1)湿重，假设样品含水量为 80%），除了十溴二苯乙烷（DBDPE）（0.6ngg(-1)干重，0.12ngg(-1)湿重）。该方法的准确性通过使用替代标准和提取物上的标准添加来对三种不同类型的加标软体动物物种进行评估，并进行定量，回收率在 70-120%范围内，除了贻贝（Ruditapes philippinarum）样品中的双（2-乙基己基）-3,4,5,6-四溴邻苯二甲酸酯（DEHTBP）（46%回收率）。此外，该方法还成功地使用三文鱼和贻贝组织的标准参考物质（SRM）对 BDE 进行了验证。最后，该方法应用于不同种类的冷冻干燥软体动物中 HFRs 的测定：贻贝（Mytilus galloprovincialis）、贻贝（Cerastoderma edule）和蛤（R. philippinarum）。筏式养殖贻贝显示出最高浓度的 HFRs（高达 0.8ngg(-1)湿重的 BDE-209）。
