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.     

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。     

超声萃取-气相色谱-质谱联用测定海洋沉积物中39种多溴联苯醚残留

建立了超声萃取-气相色谱-质谱法测定海洋沉积物中39种多溴联苯醚残留的分析方法.样品用V(正己烷):V(二氯甲烷) =1:1混合溶液提取,超声(控制水浴温度为25 ℃)提取60 min,采用硅胶和氧化铝净化,负化学离子源-气相色谱-质谱法进行检测,39种组分图谱在49 min 内能得到很好的分离. 39种混合样品的检出限为0.003～0.10 μg/kg; 加标回收率为66.2%～118.6%;相对标准偏差为0.8%～18.2%.用于实际样品分析,结果令人满意.     

Evaluation of a new carbon/zirconia‐based sorbent for the cleanup of food extracts in multiclass analysis of pesticides and environmental contaminants

A novel carbon/zirconia‐based material, Supel^TM QuE Verde, was evaluated in a filter‐vial dispersive solid‐phase extraction cleanup of pork, salmon, kale, and avocado extracts for the residual analysis of 65 pesticides and 52 environmental contaminants (flame retardants, polychlorinated biphenyls, polybrominated diphenyl ethers, and polycyclic aromatic hydrocarbons) using low‐pressure gas chromatography with tandem mass spectrometry. An amount of 180 mg sorbent per 0.6 mL extract in filter‐vial dispersive solid‐phase extraction cleanup was found the optimum in terms of achieving satisfactory removal of co‐extractives and recoveries of analytes, especially for structurally planar compounds. For analytes partially retained by Verde, normalization to an internal standard resulted in 62–107% recoveries. Addition of Verde to primary secondary amine and C₁₈ in cleanup resulted in 38% more removal of gas‐chromatography‐amenable co‐extractives in avocado, 30% in kale, 39% in salmon, and 50% in pork. The removal efficiency of co‐extracted chlorophyll was 93% for kale and 64% for avocado based on ultraviolet‐visible absorbance. The developed method was validated at three spiking levels (10, 25, and 100 ng/g), and 70–120% recoveries with ≤20% relative standard deviation were achieved for 96 (83%) out of 117 analytes in pork, 79 (69%) in salmon, 71 (62%) in kale, and 75 (65%) in avocado.     

Determination of polybrominated diphenyl ethers in river water by combination of liquid–liquid extraction and gas chromatography–mass spectrometry

In this work,a reliable and sensitive method for detecting polybrominated diphenyl ethers(PBDEs) has been developed by the combination of liquid–liquid extraction and gas chromatography–mass spectrometry.PBDEs were extracted from a large volume of water by liquid–liquid extraction and purified by silica gel chromatography.In order to reduce the deviation,dibromobiphenyl was exploited as the internal standard to minimize differences among the injections.The quantification was performed using an external standard.Good linear correlation coefficients(0.991) and a wide linearity range(1.0–500.0 ng/L) indicated the steadiness of the proposed method.Moreover,the satisfactory recovery(75%)suggested that successful determination of PBDEs in river water had been achieved.Furthermore,the deduction behavior of PBDEs in river water could be inferred according to the results.     

Gas chromatography/ion trap mass spectrometry applied for the determination of polybrominated diphenyl ethers in soil

A gas chromatography/ion trap mass spectrometry (GC/ITMS) method was developed for the determination of polybrominated diphenyl ethers (PBDEs). ITMS parameters were optimized in order to achieve the best sensitivity for the PBDE analysis. Tandem mass spectrometry, along with an isotope dilution internal standard method, was used for the quantitation. Chromatographic windows were developed for mono- to hepta-BDEs, depending on the retention times when a 30-m GC column was used. A different 15-m column was used to analyze deca-BDE. Environmental soil samples collected from an electronic waste recycling site were prepared by using Soxhlet extraction and column chromatographic cleanup. Average recoveries of 61-118% were obtained for the 13C-labeled PBDE internal standards spiked in the samples prior to sample preparation. The accuracy represented by relative analytical errors was -24% to 18%, and the precision (relative standard deviation) was 11-26% (n=8). The method detection limits ranged from 0.013-0.25 ng/g for the PBDEs in soil.     

Microwave-assisted extraction followed by headspace solid-phase microextraction and gas chromatography with mass spectrometry detection (MAE-HSSPME-GC-MS/MS) for determination of polybrominated compounds in aquaculture samples

This paper describes the first validated method for the extraction, purification and determination of trace levels of a number of pollutants of growing concern, including polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs), in aquaculture feeds and products. The new procedure comprises microwave-assisted extraction (MAE; optimized, using a central composite experimental design, to 15 min at 85 °C in 14 mL of 1:1 hexane/dichloromethane), and concentration by headspace solid-phase microextraction (HSSPME), and separation/quantification by gas chromatography with mass spectrometry detection (GC-MS/MS). The method was validated on the reference materials IAEA-406 and WMF-01. Limits of detection for fourteen of the fifteen analytes considered range from 10 to 600 pg g⁻¹, and limits of quantification from 50 pg g⁻¹ to 1.9 ng g⁻¹. Linear ranges, accuracies and precisions are reported.     

Fast analysis of polybrominated diphenyl ethers in eggs using selective pressurized liquid extraction coupled with online GPC-GC/MS

This article reports the applicability of online gel permeation chromatography (GPC)-GC/MS for the determination of seven predominant polybrominated diphenyl ethers (PBDEs) in eggs to effectively eliminate matrix interference. Selective pressurized liquid extraction using acidic alumina as a fat retainer was used for cleanup of the PBDEs in eggs. It was selected because of its advantages: simpler operation, minimum time spent on sample handing to get fat-free extracts, and low volume of solvent consumption. After concentration, the extract was directly injected for online GC/MS operated in the negative ion chemical ionization mode with a 15 m capillary column. Recoveries of spiked samples were between 75.1 and 102.0%, with RSDs (n=3) ranging from 3.69-11.47% when spiked at levels of 2 and 20 ng/g, dry mass. The LOD varied from 0.25-34 ng/g, dry mass. The proposed method was proven to be rapid, efficient, and reliable for the trace determination of PBDEs in eggs.     

Development and validation of a subcritical 1,1,1,2‐tetrafluoroethane extraction technique: Gas chromatography–mass spectrometry method for the simultaneous determination of polycyclic aromatic hydrocarbons,polychlorinated biphenyls,and polybrominated biphenyl ethers in aquatic products

A simple, rapid, and green method was developed for the simultaneous analysis of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and polybrominated biphenyl ethers in aquatic products using subcritical 1,1,1,2‐tetrafluoroethane extraction coupled with gas chromatography and mass spectrometry. Effects of the extraction temperature, pressure, and cosolvent volume on the extraction efficiency were investigated by extracting spiked oyster samples. The results show that the maximum extraction efficiency was obtained at 40°C, 12 MPa, and a cosolvent (dichloromethane) volume of 5.0 mL. Under these conditions, the calibration curves had good linearity with square of the correlation larger than 0.998 in the concentration range of 5–800 ng/mL; limit of detection and limit of quantitation were 0.16–2.83 and 0.55–9.43 ng/g, respectively. At spiked levels of 10, 30, and 50 ng/g, the average recoveries were 70.4–80.4% for polycyclic aromatic hydrocarbons, 74.0–83.6% for polychlorinated biphenyls, and 66.9–78.0% for polybrominated biphenyl ethers, with average relative standard deviations of less than 16.3%. The established method has no significant differences in recovery compared to traditional methods and is suitable for the analysis of real samples.     

Isolation and recovery of selected polybrominated diphenyl ethers from human serum and sheep serum: coupling reversed-phase solid-phase disk extraction and liquid-liquid extraction techniques with a capillary gas chromatographic electron capture negative ion mass spectrometric determinative technique

Polybrominated diphenyl ethers (PBDEs) are isolated and recovered with acceptable percent recoveries from human serum via liquid-liquid extraction and column chromatographic cleanup and fractionation with quantitation using capillary gas chromatography-mass spectrometry with electron capture negative ion and selected ion monitoring. PBDEs are found in unspiked serum. An alternative sample preparation approach is developed using sheep serum that utilizes a formic acid pre-treatment followed by reversed-phase solid-phase disk extraction and normal-phase solid-phase cleanup using acidified silica gel that yields>50% recoveries. When these percent recoveries are combined with a minimized phase ratio for human serum and very low instrument detection limits, method detection limits below 500 parts-per-trillion are realized.     

固相萃取-气相色谱-负化学源质谱法测定人血清中的多溴联苯醚

采用OasisHLB固相萃取柱萃取血清中的多溴联苯醚(PBDEs),经浓硫酸柱上除脂后,利用气相色谱-负化学源质谱法测定BDE-17、28、47、66、99、100、153、154、183和209共10种PBDEs组分。BDE-209的测定采用DB-5 ms色谱柱(15 m×0.25 mm×0.1 μm),其他组分采用VF-5 ms色谱柱(30 m×0.25 mm×0.25 μm)。对样品中蛋白质的去除溶剂和固相萃取条件(如洗脱溶剂及其用量)进行了优化。胎牛血清中的加标回收试验结果显示,各PBDEs单体相对于内标的平均回收率为78.5%～109.7%,日内测定的相对标准偏差(RSD)为0.3%～7.4%,日间测定的RSD为1.4%～14.1%。胎牛血清中三溴～七溴联苯醚的检出限(信噪比为3)为0.10～0.27 ng/L;定量限(信噪比为10)除了BDE-209为7.91 ng/L外,其他PBDEs为0.35～0.91 ng/L。采用本方法测定标准参考物质SRM1957和SRM1958,结果在参考值范围内。实验结果表明,本方法灵敏度高、准确度和精密度好,简便快速,溶剂消耗量少,适用于人体血清中三至十位溴取代联苯醚的测定。     

Optimized determination of polybrominated diphenyl ethers by ultrasound‐assisted liquid–liquid extraction and high‐performance liquid chromatography

A method based on ultrasound‐assisted liquid–liquid extraction and high‐performance liquid chromatography has been optimized for the determination of six polybrominated diphenyl ether congeners. The optimal condition relevant to the extraction was first investigated, more than 98.7 ± 0.7% recovery was achieved with dichloromethane as extractant, 5 min extraction time, and three cycles of ultrasound‐assisted liquid–liquid extraction. Then multiple function was employed to optimize polybrominated diphenyl ether detection conditions with overall resolution and chromatography signal area as the responses. The condition chosen in this experiment was methanol/water 93:7 v/v, flow rate 0.80 mL/min, column temperature 30.0°C. The optimized technique revealed good linearity (R² > 0.9962 over a concentration range of 1–100 μg/L) and repeatability (relative standard deviation < 6.3%). Furthermore, the detection limit (S/N = 3) of the method were ranged from 0.02 to 0.13 μg/L and the quantification limit (S/N = 10) ranged from 0.07 to 0.35 μg/L. Finally, the proposed method was applied to spiked samples and satisfactory results were achieved. These results indicate that ultrasound‐assisted liquid–liquid extraction coupled with high‐performance liquid chromatography was effective to identify and quantify the complex polybrominated diphenyl ethers in effluent samples.     

全二维气相色谱/飞行时间质谱法定性筛查鱼肉组织中含卤有机污染物

采用全二维气相色谱/飞行时间质谱(GC×GC-TOFMS),建立了鱼肉样品中含卤有机污染物的定性和定量分析方法.鱼肉样品用正己烷丙酮(1∶1,V/V)提取,凝胶色谱和复合硅胶柱净化,浓缩富集,全二维气相色谱联用飞行时间质谱(DB-5MS毛细管色谱柱联HT-8色谱柱)检测.软件自动识别后,经三步筛查,共鉴定出含氯或溴化合物72种,其中包括33种多氯联苯,9种有机氯农药,4种多溴联苯醚,4种DDT代谢产物,2种氯代茴香醚,2种氯苯乙烯,1种氯代茴香硫醚及1种甲基三氯生.另外,从质谱信息上看,有16种化合物明显含氯或含溴,但是因为缺少必要的谱库信息不能准确识别.采用外标定量法,对鱼肉样品中检出的主要的10种多氯联苯和1种多溴联苯醚进行了准确定量分析.     

Analysis of persistent halogenated hydrocarbons in fish feeds containing fish oil and other alternative lipid sources

A trade-off exists between beneficial n-3 long-chain polyunsaturated acids and toxic persistent halogenated hydrocarbons (PHHs), both of which primarily originate from fish oil commonly used in fish feeds. Alternative lipid sources are being investigated for use in fish feeds to reduce harmful contaminant accumulation, hence, research is needed to evaluate PHHs in fish feeds with various lipid compositions. An analytical method was developed for PHHs including nine organochlorine insecticides (OCPs), 26 polychlorinated biphenyls (PCBs) and seven polybrominated diphenyl ethers (PBDEs) in fish feeds with differing proportions of fish oils and alternative lipid sources by GC-ECD after accelerated solvent extraction, gel permeation chromatography (GPC), and sulfuric acid cleanup. The GPC removed the majority of the neutral lipids and sulfuric acid treatment effectively destroyed the polar lipids. Thus, the combination of the two methods removed approximately 99.7% of the lipids in the extracts. The method detection limits were less than 5 ng/g dry weight (dw) for most PHHs, while recoveries were 75-118%, 67-105%, 69-92%, 63-100% and 94-144% with relative standard deviations of 0.2-39%, 0.3-20%, 0.5-12%, 1.5-18% and 1.5-15% for PHHs in five types of fish feeds made from different lipid sources. Although the source of lipid showed no impact on cleanup efficiency and the developed method worked well for all feeds, fish feeds with 100% fish oil contained background PHHs and more interference than feeds containing alternative lipids.     

Determination of PBDEs in human breast adipose tissues by gas chromatography coupled with triple quadrupole mass spectrometry

The potential of gas chromatography/tandem mass spectrometry with a triple quadrupole analyzer for determination of 12 polybrominated diphenyl ethers in human breast tissues has been investigated. After extraction with hexane, two purification procedures-automated normal-phase high-performance liquid chromatography and solid-phase extraction-were assayed. Both electron impact ionization, in selected reaction monitoring mode, and negative chemical ionization, in selected ion recording mode, were tested for the optimum determination of analytes. Isotopically labeled standards were added before extraction as surrogates: [¹³C]BDE47, [¹³C]BDE99 and [¹³C]BDE153 for electron impact ionization, and p,p′-DDE-d ₈ for negative chemical ionization. The method was validated in terms of accuracy, precision, limits of detection and limits of quantification, using human breast tissue spiked at three levels in the range 1–50 ng/g (5–250 ng/g for BDE209). The analytical approach using solid-phase extraction cleanup followed by gas chromatography/mass spectrometry (negative chemical ionization ) led to lower detection limits (0.006–2 ng/g) and allowed the determination of the most problematic congener, BDE209, whose poor sensitivity made difficult its determination at low residue levels. Special attention was given to the confirmation of the compounds detected in samples in order to avoid reporting false positives. Two tandem mass spectrometry transitions or three m/z ions were selected for each analyte when using electron impact ionization or negative chemical ionization modes, respectively. In both cases, the transition to ion intensity ratio was used as a confirmation parameter. The method developed was applied to the analysis of real human samples. Several brominated diphenyl ethers (congeners 47, 100, 99, 154, 153, 183 and 209) were detected in the range 0.08–0.23 ng/g.     

新型双嘧啶酮二苯醚的合成

以自制的4,4'-双甲酰基二苯醚类化合物、β-酮酸酯及脲为原料,在Fe C13·6H2O的催化下,通过Biginelli反应合成了12种新型双嘧啶酮二苯醚类衍生物(6a~6l),探讨了双嘧啶酮合成的反应历程并对反应条件进行优化.另外,对4,4'-双甲酰基二苯醚类化合物的合成方法进行了改进,通过控制对氟苯甲醛的加入时间,提高了产率,并大大缩短了反应时间.对所有化合物进行了室内毒力测试,结果表明,化合物6d,6h和6i的抗菌效果较好,对西瓜枯萎病的EC95值均小于对照药三唑酮;当取代基R2为CF3时,化合物的杀菌抑菌活性较好.     

Determination of Ochratoxin A in Human Blood Serum by High-Performance Liquid Chromatography: Method Validation and Comparison of Extraction Procedures

Abstract

A high-performance liquid chromatography method for determination of ochratoxin A (OTA) in human blood serum has been validated. A liquid-liquid partition, solid-phase extraction and immunoaffinity cleanup was applied for OTA extraction from 0.5 mL of serum. Significant correlation (r = 0.998) was found over the range from 0.1 to 8 ng/mL, with better performance in terms of accuracy, precision, and selectivity. Validation was made with human serum spiked at two levels, 0.5 and 2.0 ng/mL,26 and natural contaminated serum. Average recoveries of OTA using different extraction methods ranged from 58.48 ± 4.56 to 94.85 ± 3.52%. Immunoaffinity cleanup showed a better recovery rate, with a lower detection limit validated at 0.1 ng/mL. The cited method can be used as a rapid and noninvasive tool to assess human and animal exposure to OTA.     

多溴联苯醚代谢物的色谱保留和质谱特征

研究了多溴联苯醚(PBDEs)代谢物中常见的18种羟基PBDEs(HO-BDEs)、15种甲氧基PBDEs(MeO-BDEs)的气相色谱、反相液相色谱分离和质谱碎片特征。MeO-BDEs在反相液相色谱(RPLC)的保留行为受疏水作用支配,而HO-BDEs则还受到除疏水作用以外的特殊作用影响。LC/MS中大气压化学电离(APCI)源适用于HO-BDEs检测,而APCI源以及电喷雾离子源(ESI)对MeO-BDEs都没有响应。质谱碎片具有显著取代位效应:在LC/APCI-MS中,邻位取代HO-BDEs的碎片离子基峰均为脱一个溴的结构[M-H]--HBr,而对位取代的基峰则为准分子离子[M-H]-;在电子电离(EI)源质谱仪下,邻位取代MeO-BDEs有脱溴甲烷碎片离子(M. -BrCH3),对位取代有特征的脱甲基自由基结构(M. -.CH3),间位取代则无上述两种碎片离子。     

同位素内标-气相色谱-高分辨双聚焦磁质谱法检测血清中多溴联苯醚

建立了同位素内标-气相色谱-高分辨双聚焦磁质谱(GC-HRMS)同时测定人体血清中14种多溴联苯醚(PBDEs)的方法.血清样品解冻后,取0.5 mL与13 C标记的内标物进行混合,加入甲醇沉淀样品中的蛋白质,比较了3种酸化条件下的去脂效果和回收率,结果显示硫酸去脂效果最好;使用液液萃取法提取样品中的目标物,比较了不同...     

超声辅助碱解萃取-气相色谱-电子捕获检测器测定海洋沉积物中8种多溴联苯醚

将超声辅助碱液分解杂质与溶剂萃取相结合,采用气相色谱-电子捕获检测(GC-ECD)建立了一种快速高效净化、萃取海洋沉积物中8种常见多溴联苯醚(PBDEs)的分析方法。样品在2.00 mol/L NaOH甲醇溶液中超声30 min,经正己烷萃取、单层硅胶净化、正己烷洗脱、旋蒸浓缩后定容至100 μL,采用GC-ECD分析。结果表明,PBDEs各单体的加标回收率为63.6%~110.3%,相对标准偏差(RSD)为1.7%~15.5%(n=5);十溴联苯醚(BDE-209)的检出限为0.097 ng/g,其他7种单体的检出限为0.002~0.011 ng/g(信噪比为3)。该方法的准确度和精密度较高,稳定性和回收率良好,可满足沉积物中PBDEs的分析要求。利用建立的方法测定了渤海表层沉积物中PBDEs的含量,8种PBDEs总含量在1.566~6.760 ng/g之间,其中BDE-209的含量为1.461~6.438 ng/g,总体呈现出由近岸向远岸递减的趋势,表明人为活动、表层冲刷和陆地河流的输入对渤海地区PBDEs的含量有重要影响。