A cleanup method of serum extracts with molecular sieves as SPE sorbents for the analysis of polybrominated diphenyl ethers

Based on the size- and shape-selective sorption, 13X molecular sieves were developed as solid-phase extraction adsorbents to cleanup serum extract for the determination of polybrominated diphenyl ethers. The important parameters affecting the cleanup efficiency were investigated including the amount of sorbents, the type, and volume of solvents. Under the optimized conditions, the capacity for removing impurities was evaluated via gel permeation chromatography and gas chromatography with mass spectrometry. The results demonstrated that up to 99% of lipids in corn oil (13 mg) can be removed after cleanup, and endogenous compounds in serum can also be effectively eliminated. The cleanup efficiency is not only superior to hydrophile-lipophile balance column, but also close to acid silica gel and multifunction impurity sorbents. Generally, the developed cleanup method exhibited higher recovery for polybrominated diphenyl ethers with more than four bromines, especially for nona- and deca-brominated diphenyl ethers (99.1˗117.8%). The cleanup method can be coupled with gas chromatography and tandem mass spectrometry for polybrominated diphenyl ethers analysis in human serum. The method detection limits were 0.01˗0.27 ng/mL and average recovery was 50.9˗113.3%, except 2,3',4',6-tetrabrominated, 2,3',4,4',6-pentabrominated, and 2,3,3',4,4',5',6-heptabrominated diphenyl ethers. 2,2',4,5'-Tetrabrominated diphenyl ethers had the highest detection frequency (95%) in human serum, whereas decabrominated diphenyl ethers had the maximum mean concentration (0.50 ng/mL).     

多溴代双羟基二苯醚的合成与抑菌活性研究

自1981年Brad等[1]首次报道从一种名为Dysides的海洋海绵体中分离出两种天然多溴代2,2′-二羟基二苯醚以来,许多科学家对此类化合物进行了大量的研究,发现它们具有较好的抑菌杀菌能力[2],杀菌效果很好,稳定性好,毒性低,对皮肤无刺激性,无致敏性、无腐蚀性,能抑制致癌的肌苷酸脱     

Comprehensive two-dimensional gas chromatography of polybrominated diphenyl ethers

Comprehensive two-dimensional gas chromatography with micro electron-capture detection (GCxGC-muECD) was evaluated for the separation of 125 polybrominated diphenyl ethers (PBDEs). From among the six column combinations that were evaluated, DB-1x007-65HT was found to be the most suitable because of: (i) the highest number of BDE congeners separated; (ii) the least decomposition of higher brominated congeners; and (iii) the most suitable maximum operating temperature. The separation of the 125 BDE congeners from five hydroxy- and two methoxy-BDEs and nine other brominated flame retardants (polybrominated biphenyls, tetrabromobisphenol-A, methyl-tetrabromobisphenol-A and hexabromocyclododecane) was also studied. Fluorinated BDEs were found to be valuable internal standards for the determination of BDEs because of their very similar physico-chemical properties and excellent separation from the parent BDEs, mainly in the second dimension. GCxGC-time-of-flight MS and GCxGC-muECD were shown to be useful tools to identify decomposition products of nona- and deca-substituted BDEs, which are formed during the GC run. Three nona-BDEs were shown to be the major decomposition products of BDE 209.     

Na2S还原法合成氨基二苯醚类化合物

氨基二苯醚不仅自身具有良好的杀菌、杀虫功效,广泛地应用到医药及农业领域。一般通过还原硝基二苯醚得到,但现有制备方法存在一些问题。Na2S作为一种较成熟的还原剂,价格低廉,反应后生成的Na2S2O3可作化工原料。本文用Na2S作为还原剂,合成路线如下：     

Na2S还原法合成氨基二苯醚类化合物

用Na2S还原硝基二苯醚类化合物，成功地合成了一系列氨基二苯醚类化合物，产率在70％以上，产物结构经IR，1H NMR和MS表征。     

邻苯二酚双苯醚的合成与抑菌活性研究

以硝基氯苯和羟基二苯醚为底物合成了6个硝基邻苯二酚双苯醚类化合物、6个氨基邻苯二酚双苯醚类化合物和6个羟基邻苯二酚双苯醚类化合物,所有这些新化合物的结构经元素分析、红外光谱、质谱及1H NMR确证.并研究了它们的抑菌活性,初步生物活性测试表明硝基、氨基芳醚类化合物的抑菌或杀菌活性较差,而羟基芳醚类化合物却有强的抑菌能力.     

A rapid method for the determination of brominated flame retardant concentrations in plastics and textiles entering the waste stream

Due to new European legislation, products going to waste are subject to ‘low persistent organic pollutant concentration limits’. Concentrations of restricted brominated flame retardants in waste products must be determined. A rapid extraction and clean‐up method was developed for determination of brominated flame retardants in various plastics and textiles. The optimised method used vortexing and ultrasonication in dichloromethane followed by sulfuric acid clean‐up to determine target compounds. Poly‐brominated diphenyl ethers were determined by gas chromatography with mass spectrometry and hexabromocyclododecane by liquid chromatography with tandem mass spectrometry. Good recoveries of target analytes were obtained after three extraction cycles. The method was validated using poly‐propylene and poly‐ethylene certified reference materials as well as previously characterised textiles, expanded and extruded poly‐styrene samples. Measured concentrations of target compounds showed good agreement with the certified values indicating good accuracy and precision. Clean extracts provided low noise levels resulting in low limits of quantification (0.8–1.5 ng/g for poly‐brominated diphenyl ethers and 0.3 ng/g for α‐, β‐ and γ‐hexabromocyclododecane). The developed method was applied successfully to real consumer products entering the waste stream and it provided various advantages over traditional methods, including reduced analysis time, solvent consumption, minimal sample contamination and high sample throughput, which is crucial to comply with the implemented legislation.     

Simple and fast analysis of tetrabromobisphenol A,hexabromocyclododecane isomers,and polybrominated diphenyl ethers in serum using solid‐phase extraction or QuEChERS extraction followed by tandem mass spectrometry coupled to HPLC and GC

Two simplified sample preparation procedures for simultaneous extraction and clean‐up of tetrabromobisphenol A, α‐, β‐, and γ‐hexabromocyclododecane and polybrominated diphenyl ethers in human serum were developed and validated. The first procedure was based on solid‐phase extraction. Sample extraction, purification, and lipid removal were carried out directly on an Oasis HLB cartridge. The second procedure was a quick, easy, cheap, effective, rugged, and safe‐based approach using octadecyl‐modified silica particles as a sorbent. After sample extraction and cleanup, tetrabromobisphenol A/hexabromocyclododecane was separated from polybrominated diphenyl ethers by using a Si‐based cartridge. Tetrabromobisphenol A and hexabromocyclododecane were then detected by high‐performance liquid chromatography coupled to tandem mass spectrometry, while polybrominated diphenyl ethers were detected by gas chromatography coupled to tandem mass spectrometry. The results of the spike recovery test using fetal bovine serum showed that the average recoveries of the analytes ranged from 87.3 to 115.3% with relative standard deviations equal to or lower than 13.4 %. Limits of detection of the analytes were in the range of 0.4–19 pg/mL except for decabromodiphenyl ether. The developed method was successfully applied to routine analysis of human serum samples from occupational workers and the general population. Extremely high serum polybrominated diphenyl ethers levels up to 3.32 × 10⁴ ng/g lipid weight were found in occupational workers.     

食品中多溴联苯醚残留的气相色谱-串联质谱分析方法研究

建立了食品中8种多溴联苯醚(PBDEs) 残留的气相色谱-串联质谱分析方法,初步解析了PBDEs的电子轰击串联质谱(EI MS/MS)图,为各种目标物的准确定性分析提供依据.以BDE-28、BDE-47、BDE-66、BDE-85、BDE-99、BDE-100、BDE-153、BDE-154为研究对象,对EI MS/MS各分析参数进行了优化.用超声提取-酸性硅胶层析柱净化的前处理方法制备样品,当空白样品的加标水平为10.0、25.0 μg/kg时,8种PBDEs的平均加标回收率为82% ～112%,相对标准偏差为3.1% ～15%,方法检出限均低于1.5 μg/kg;8种PBDEs的线性范围为10.0 ～500 μg/kg,相关系数均大于0.994 7.     

溴代二羟基硝基二苯醚类化合物的合成与抑菌活性研究

综合考虑二苯醚类杀菌剂结构与活性关系的前期研究结果, 以双羟基二苯醚为原料, 经酸酐保护、硝化、去保护得到含硝基的双羟基二苯醚, 再经过溴代反应合成了7个新的溴代2,2'-, 2,4'-和4,4'-二羟基硝基二苯醚; 所有这些化合物的结构均经¹H NMR, MS, IR和元素分析所证实; 并检测了合成的溴代二羟基硝基二苯醚化合物对两种有害菌的抑菌活性, 结果表明: 它们对所测试菌种具有优良的抑制效果, 其中3个化合物在质量分数为5×10^－6的浓度下抑菌率超过100%, 能完全控制细菌的生长.     

Gas chromatographic retention of 180 polybrominated diphenyl ethers and prediction of relative retention under various operational conditions

The gas chromatographic (GC) retention times of 180 polybrominated diphenyl ethers (PBDEs) were obtained under different operational conditions on two types of commonly used capillary columns, Restek Rtx-1614 and J&W DB-5MS, of different dimensions. The relative retention times (RRTs) for PBDEs were calculated by normalizing the retention times of individual congeners to the sum of those of BDEs 47 and 183. In clear contrast to polychlorinated biphenyls (PCBs), the elution of PBDEs has few cross-homolog overlaps, and this observation is discussed in terms of molecular conformation with regard to co-planarity. Within a homolog, ortho substitution in PBDEs tends to decrease GC retention, and such an effect is stronger for higher homologs. With the RRT database established in this work, a simple approach is evaluated for the identification of all mono to hepta PBDEs from the RRTs of 39 congeners under various GC conditions to facilitate the identification of unknown PBDE peaks for which chemical standards are not available.     

同位素稀释-高分辨气相色谱/高分辨质谱法测定大气中多溴联苯醚和多溴联苯153

针对环境监测的特点和要求,建立了同位素稀释-高分辨气相色谱/高分辨质谱测定大气中多溴联苯醚(PBDEs)和多溴联苯153(BB153)的方法。采用正己烷/二氯甲烷(1:1, v/v)及正己烷分别对PBDEs和BB153进行快速溶剂萃取,并通过复合硅胶柱净化。在校准曲线最高浓度的10%和90%加标水平下得到的天然内标的平均回收率分别为100%和104%,平均相对标准偏差(n=7)分别为5%和6%;二至十溴代联苯醚和BB153相应的¹³C同位素标准物质回收率在36.5%~133%之间;而一溴代联苯醚¹³C同位素标准物质回收率较差,可能是由于物化性质与其他化合物不同。在实际采样体积为300 m³的情况下,未发生污染物穿透现象;分析物检出限低于2×10^-4 ng/Nm³,提取内标回收率在56%~126%之间(一溴代联苯醚除外)。实验结果表明该方法能对化合物准确定量,适用于大气中二至十溴代联苯醚和BB153的分析。     

Determination of polybrominated diphenyl ethers in environmental standard reference materials

Standard reference materials (SRMs) are valuable tools in developing and validating analytical methods to improve quality assurance standards. The National Institute of Standards and Technology (NIST) has a long history of providing environmental SRMs with certified concentrations of organic and inorganic contaminants. Here we report on new certified and reference concentrations for 27 polybrominated diphenyl ether (PBDE) congeners in seven different SRMs: cod-liver oil, whale blubber, fish tissue (two materials), mussel tissue and sediment (two materials). PBDEs were measured in these SRMs, with the lowest concentrations measured in mussel tissue (SRM 1974b) and the highest in sediment collected from the New York/New Jersey Waterway (SRM 1944). Comparing the relative PBDE congener concentrations within the samples, we found the biota SRMs contained primarily tetrabrominated and pentabrominated diphenyl ethers, whereas the sediment SRMs contained primarily decabromodiphenyl ether (BDE 209). The cod-liver oil (SRM 1588b) and whale blubber (SRM 1945) materials were also found to contain measurable concentrations of two methoxylated PBDEs (MeO-BDEs). Certified and reference concentrations are reported for 12 PBDE congeners measured in the biota SRMs and reference values are available for two MeO-BDEs. Results from a sediment interlaboratory comparison PBDE exercise are available for the two sediment SRMs (1941b and 1944).     

新型溴代羟基二苯醚的合成及抑菌活性研究

设计并合成了10个新的溴代羟基二苯醚, 所有这些化合物的结构均经过¹H NMR, MS, IR和元素分析所证实. 新化合物的结构避免了现有卤代2-羟基二苯醚杀菌剂在生产和使用过程中有可能生成高毒性二噁英类化合物的缺点. 选择几种有害菌对合成的溴代羟基二苯醚进行了抑菌活性检测, 证实它们对所测试菌种具有优良的抑制效果.     

Retention-time database of 126 polybrominated diphenyl ether congeners and two bromkal technical mixtures on seven capillary gas chromatographic columns

The elution order of 126 polybrominated diphenyl ethers (PBDE) was determined for seven different gas chromatographic (GC) stationary phases. The resulting database facilitates selection of the most suitable GC columns for developing a quantitative, congener-specific BDE analysis and the testing of retention prediction algorithms based on structure relationships of GC phases and congener substitution patterns. In addition, co-elutions of the principal BDE congeners with other BDEs and/or with other brominated flame retardants were investigated and, as an application, the composition of two Bromkal mixtures (70-5DE and 79-8DE) was studied.     

“One-shot” analysis of polybrominated diphenyl ethers and their hydroxylated and methoxylated analogs in human breast milk and serum using gas chromatography-tandem mass spectrometry

The presence of polybrominated diphenyl ethers (PBDEs) and their hydroxylated (OH-BDE) and methoxylated (MeO-BDE) analogs in humans is an area of high interest to scientists and the public due to their neurotoxic and endocrine disrupting effects. Consequently, there is a rise in the investigation of the occurrence of these three classes of compounds together in environmental matrices and in humans in order to understand their bioaccumulation patterns. Analysis of PBDEs, OH-BDEs, and MeO-BDEs using liquid chromatography-mass spectrometry (LC-MS) can be accomplished simultaneously, but detection limits for PBDEs and MeO-BDEs in LC-MS is insufficient for trace level quantification. Therefore, fractionation steps of the phenolic (OH-BDEs) and neutral (PBDEs and MeO-BDEs) compounds during sample preparation are typically performed so that different analytical techniques can be used to achieve the needed sensitivities. However, this approach involves multiple injections, ultimately increasing analysis time. In this study, an analytical method was developed for a “one-shot” analysis of 12 PBDEs, 12 OH-BDEs, and 13 MeO-BDEs using gas chromatography with tandem mass spectrometry (GC-MS/MS). This overall method includes simultaneous extraction of all analytes via pressurized liquid extraction followed by lipid removal steps to reduce matrix interferences. The OH-BDEs were derivatized using N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (TBDMS-MTFA), producing OH-TBDMS derivatives that can be analyzed together with PBDEs and MeO-BDEs by GC-MS/MS in “one shot” within a 25-min run time. The overall recoveries were generally higher than 65%, and the limits of detection ranged from 2 to 14 pg in both breast milk and serum matrices. The applicability of the method was successfully validated on four paired human breast milk and serum samples. The mean concentrations of total PBDEs, OH-BDEs, and MeO-BDEs in breast milk were 59, 2.2, and 0.57 ng g⁻¹ lipid, respectively. In serum, the mean total concentrations were 79, 38, and 0.96 ng g⁻¹ lipid, respectively, exhibiting different distribution profiles from the levels detected in breast milk. This “one-shot” GC-MS/MS method will prove useful and cost-effective in large-scale studies needed to further understand the partitioning behavior, and ultimately the adverse health effects, of these important classes of brominated flame retardants in humans.     

溴氯混合卤代羟基二苯醚抑菌剂的合成

氯代羟基二苯醚以其优越的杀菌能力,广谱性和低毒性广泛应用于化妆品,洗涤剂,医药,医疗器械等领域。     

Preparation and applications of perfluorinated ion doped polyaniline based solid-phase microextraction fiber

A perfluorooctanesulfonic acid-doped polyaniline (PFOS-doped PANI) directly electrodeposited onto stainless steel was employed as a solid-phase microextraction (SPME) fiber. Commercial SPME fibers were chosen to compare with the PFOS-doped PANI through extraction of phenols and polybrominated diphenyl ethers (PBDEs). Excellent extraction efficiency of this fiber was demonstrated, indicating its good affinity for both non-/less polar and polar compounds. To achieve maximum response, influential parameters affecting the extraction efficiency were optimized by full-factorial experimental designs. Under the optimized conditions, the analytical features for PBDEs were estimated. The calibration curve was linear approximately 3 orders of magnitude for the target analytes, with linear correlation coefficients greater than 0.99. Detection limits in the range of 0.1–0.2 ng/L were obtained. Repeatability (n = 5) was in the range of 4.5–8.3%. The results suggest that the proposed fiber can be applied for the determination of trace PBDEs in environmental water and expected to be extended to other analytes and matrices.     

Effect of the Structure of Benzo- and Dibenzocrown Ethers on Their Reaction with the Aerosil Surface

The adsorption of 4-substituted benzo- and 5,5′-disubstituted dibenzocrown ethers from benzene by aerosil A-300 was studied. The ethers included a total of 45 compounds with diphenyl oxide, diphenyl, and diphenyl sulfide fragments. Analysis of the Henry coefficients (K_H) and the extent of desorption, the IR spectra of the adsorbed compounds, and the relationship between their structure and adsorption capacity indicated that all structural fragments of the crown ethers studied interact to some extent with aerosil surface fragments. The number of oxygen atoms in the polyether fragment and the size of the macrocycle are the predominant factors. A large, nonadditive increase in K_H is observed in going from pentadentate to hexadentate crown ethers. __________ Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 41, No. 4, pp. 247–251, July–August, 2005.     

人体血清中的多溴联苯醚、邻苯二甲酸酯和双酚A的连续在线分离及气相色谱-质谱测定

建立了人体血清中多种环境雌激素:多溴联苯醚、邻苯二甲酸酯和双酚A的快速可靠的连续在线分离及在气相色谱-质谱上的分析方法.血清样品经过浓盐酸使蛋白质变性,用乙醚萃取,经硅胶柱分离出多个族组分:多溴联苯醚(Polybrominated diphenyl ethers,PBDEs)、邻苯二甲酸酯(Phthalate estcrs,PAEs)和双酚A(Bisphenol A,BPA),最后由气相色谱-质谱的选择离子检测测定.PBDEs,PAEs和BPA标准曲线回归方程拟合度R2均大于0.99,表明在测试的浓度范围内线性关系良好.PBDEs目标化合物的检出限为0.005～0.048μg/L,PAEs目标化合物的检出限为0.103～0.833μg/L,BPA的检出限是0.035 μg/L.标准样品重复样中,PBDEs的RSD(relative standard deviation)值分别为2.8％～10.9％;PAEs的RSD值为5.6％～9.9％;BPA的RSD值为3.0％.实际血清样品中,PBDEs的加标回收物PCB209(Polychloride diphenyl ether 209)的回收率范围是74.8％～88.5％;PAEs中的加标回收物DBP-D4(Dibutyl phthalateDeutorium 4)的回收率范围为78.7％～97.0％;BPA中的加标回收物BPA-D16( Bisphenol A-Deutorium 16)的回收率范围是76.3％～93.1％.本方法检测血液中多种环境雌激素灵敏度高、重现性和回收率均良好.