蔬菜中多溴联苯醚的定量测定及其对人体的生物有效性

建立了以索氏抽提,凝胶渗透色谱及硅胶-氧化铝复合层析柱净化,测定蔬菜中13种多溴联苯醚(PBDEs)的GC-NCI MS分析方法,方法的检出限以干重计为5.4 ～15.7 pg/g,加标样品的回收率和RSD分别为78% ～97%和0.6% ～10.0%.还研究了蔬菜中的PBDEs在人胃肠中对人体的生物有效性,胡萝卜和菠菜中PBDEs的总含量分别为424.1 pg/g和981.3 pg/g,对人体的平均生物有效性分别为33.5%和2.6%,计算得到13种PBDEs在胡萝卜和菠菜中的生物有效含量分别为132.6 pg/g和26.1 pg/g,研究结果对污染物的暴露风险评估有参考价值.     

大流量采样高分辨气相色谱/高分辨质谱法测定大气中的多氯联苯和多溴联苯醚

建立了大流量空气采样高分辨气相色谱/高分辨质谱(HRGC/HRMS)同时分析测定大气样品中多氯联苯(PCBs)和多溴联苯醚(PBDEs)的分析方法。结果表明在采样过程中污染物没有发生穿透。通过添加 13C同位素标准物质进行评价,PCBs和PBDEs的加标回收率分别为60.7%～121.4%和69.9%～140.4%,均符合美国环保署相关方法的要求。PCBs和PBDEs的方法检出限分别低于0.019 pg/m3和0.189 pg/m3;色谱分离效果良好,可以满足大气样品中PCBs和PBDEs的监测需要。     

固相萃取结合超高效液相色谱-串联质谱法及气相色谱-负化学源质谱法测定人血清中的四溴双酚A、六溴环十二烷和多溴联苯醚

建立了固相萃取同时提取、净化血清中四溴双酚A(TBBPA)、α, β, γ-六溴环十二烷(HBCD)和8种多溴联苯醚(PBDEs)同系物的样本前处理方法,并结合色谱-质谱分离分析技术检测人血清样本中该类化合物的含量。试样在加入各自的同位素内标物后以甲基叔丁基醚/正己烷(1:1, v/v)混合溶剂进行萃取,再经浓硫酸去除脂肪后,以LC-Si固相萃取柱分离HBCD/TBBPA和PBDEs。采用分步检测的方式,在50 mm长BEH C18反相色谱柱上以超高效液相色谱-串联质谱(UPLC-MS/MS)的多反应监测模式(MRM)检测HBCD和TBBPA,在15 m长的毛细管柱上以气相色谱-负化学源质谱(GC-NCI/MS)的选择离子监测模式(SIM)检测PBDEs。以胎牛血清为空白基质,当HBCD、TBBPA和BDE-209的加标水平为0.5 ng/g和5 ng/g、三溴至七溴联苯醚的加标水平为0.05 ng/g和0.5 ng/g时,它们的平均加标回收率为80.3%～108.8%,相对标准偏差为1.02%～11.42%(n=5);以信噪比(S/N)为3计算,方法的检出限(LOD)为1.81～42.16 pg/g。采用该方法对实际样品进行测定,结果表明,本方法快速、准确、灵敏度高,能够满足血清中HBCD、TBBPA和PBDEs残留的同时提取及测定的要求。     

气相色谱-质谱法检测沉积物中自由态与束缚态多溴联苯醚和四溴双酚-A

建立了一种同时测定沉积物中不同赋存形态的多溴联苯醚(PBDEs)和四溴双酚A(TBBPA)的分析方法.样品由等体积的丙酮和正己烷混合溶剂抽提得到自由态目标物,再通过碱性水解反应释放束缚态目标化合物.通过调节酸度(pH值)实现PBDEs和TBBPA的分离和提取.PBDEs由复合硅胶柱净化,运用气相色谱-质谱(负离子化学源)-分时段选择离子监测技术测定;TBBPA经重氮甲烷衍生化反应后由酸性硅胶柱预纯化,运用气相色谱-质谱(电子轰击源)-分时段选择离子监测技术测定.8种低溴联苯醚(BDE28,-47,-66,-100,-99,-154,-153,-183),十溴联苯醚(BDE209)和TBBPA的检出限分别为0.6～12.5 pg/g,172 pg/g,4 2 pg/g.方法具有良好的准确度和精确度,回收率均在74%～106%之间,RSD≤10%.对东江沉积物样品的分析表明,本方法能够实现不同形态的PBDEs 和TBBPA的有效检测.     

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。     

母乳中多种含卤持久性有机污染物的联合检测方法

建立了母乳中多种含卤持久性有机污染物(POPs)的联合检测方法,目标化合物主要包括六溴环十二烷(HBCDs)、多溴联苯醚(PBDEs)、多氯联苯(PCBs)和有机氯农药(OCPs)等.样品的前处理采用液液萃取、凝胶渗透色谱(GPC)净化和固相萃取(SPE)等技术,目标化合物经气相色谱-质谱联用仪(GC-MS)、液相色谱-三重四极杆串联质谱联用仪(LC-MS/MS)和气相色谱-三重四极杆串联质谱联用仪(GC-MS/MS)等进行检测.样品通过GPC除去脂肪,然后经SPE柱进一步净化并进行多组分分离,极大程度地减小了生物样品中复杂基质的干扰,适合样品量相对较小的人体样本中多种超痕量POPs的分析.应用灵敏度高、选择性更好的GC-MS/MS对样品中的PCBs和OCPs等进行分析,进一步降低基质的干扰.方法经过小牛血清加标实验验证,稳定可靠.POPs的加标回收率分别为88.7％～98.8％(PBDEs), 88.5％～92.5％(HBCDs), 67.9％～82.3％(PCBs)和81.7％～116.1％(OCPs),方法检出限分别为0.13～1.8 pg/mL(PBDEs), 0.31～1.2 pg/mL(HBCDs), 0.22～1.4 pg/mL(PCBs)和0.20～1.5 pg/mL(OCPs).采用本方法对潍坊地区20例母乳样品进行分析,结果显示,潍坊市母乳中HBCDs, PBDEs, PCBs、HCHs和DDTs的中值浓度分别为2.86, 7.76, 8.84、140和503 ng/g 脂重,此浓度水平与国内其它地区人群相当.     

大流量采样-GC-NCI-MS测定环境空气中的多溴联苯醚

建立了大流量采样-气相色谱负化学电离质谱法测定环境空气中痕量多溴联苯醚的方法.用PS-1型大流量空气采样器采集环境空气样品,样品经提取、纯化后采用气相色谱负化学电离质谱法测定环境空气中多溴联苯醚.方法的线性范围在5～10000 pg/m3之间,检出限1～50 pg/m3.用于检测2006年5月在广州市采集的环境空气样品,多溴联苯醚组分含量在5.4～4989 pg/m3范围.该方法适合用于监测环境空气中的痕量PBDEs.     

海产品中九种多溴联苯醚残留的气相色谱-负化学离子源／质谱法分析

建立了海产品中九种多溴联苯醚(PBDEs)残留的气相色谱-负化学离子源/质谱(GC-NCI/MS)分析方法.采用正己烷提取剂超声提取、Florisil硅藻土净化柱净化和正己烷洗脱剂洗脱的样品前处理方法,以PCB-103作为内标物,以GC-NCI/MS的选择离子监测方式(S1M)对海产品中九种PBDEs残留进行了定性与定量分析.分析方法的线性相关系数均≥0.9988,九种PBDEs两种添加浓度水平时的平均加标回收率为88.1%～97.3%,相对标准偏差为2.0%～6.6%,方法检出限均小于0.106 ng/g.线性范围除PBDE-183为0.60～300.0 ng/g外,其余八种PBDEs为0.50～250.0 ng/g.同时分析了紫菜、海带、鲜海带、鱼干和花蛤干等海产品,在这些海产品干货中都检出了较多种的PBDEs残留.     

超声辅助萃取气相色谱-质谱法测定松针中的多溴联苯醚

建立了测定松针样品中多溴联苯醚(PBDEs)的分析方法。松针样品经过正己烷-丙酮(体积比为1∶1)混合溶液超声萃取、浓硫酸和氧化铝柱净化后,采用气相色谱-负化学电离源质谱(GC-NCI-MS)选择离子监测(SIM)模式检测,内标法定量。结果表明,方法的加标回收率为83.8%~107.5%,三溴~七溴代联苯醚的仪器检出限为0.152~ 0.770 pg,十溴代联苯醚(BDE-209)的检出限为11.1 pg;三溴~七溴代联苯醚的方法检出限(湿重)为3~15 pg/g,BDE-209的方法检出限(湿重)为222 pg/g。方法具有良好的重现性、较高的灵敏度和良好的回收率。实际样品分析表明,松针中BDE-209是主要的同类物,约占8种PBDEs总量的82.3%,低溴代联苯醚以2,2′,4,4′-四溴联苯醚(BDE-47)为主。     

凝胶渗透色谱结合气相色谱-负化学源质谱法分析鱼肉及鱼油中的多溴联苯醚和得克隆阻燃剂

建立了凝胶渗透色谱(GPC)结合气相色谱-负化学源质谱(GC-NCI/MS)检测鱼肉及鱼油中8种多溴联苯醚(PBDEs)同系物及2种得克隆阻燃剂(DP)的分析方法。试样中加入内标物BDE-77和13C12-BDE-209后进行索氏提取,提取液经自动GPC系统除脂,多层硅胶层析柱净化后,在15 m长的毛细管气相色谱柱上分离,NCI/MS以选择离子监测方式检测目标化合物。以鱼肉样品为基质,当PBDEs的加标水平为0.2 ng/g和2 ng/g、BDE-209和DP的加标水平相应提高10倍时,其平均加标回收率为71.1%～121.4%,相对标准偏差为2.96%～13.31%(n=5);以信噪比(S/N)为3计算方法的检出限(LOD)为2.2～39.8 ng/kg。用该方法检测市售鱼肉及鱼油样品,其中多溴联苯醚总含量为2.18～15.93 ng/g,以BDE-209、BDE-47为主,两种DP均未检出。该方法准确、灵敏度高,能够满足富含脂质的动物性样品中痕量DP和PBDEs残留的分析要求。     

气相色谱/离子阱串联质谱法检测大气中的多溴二苯醚

运用气相色谱-离子阱质谱(ion trap mass spectrometry,ITMS)建立了大气中8种多溴二苯醚的二级质谱(MS/MS)检测方法。优化后的MS/MS方法对7种三溴至七溴二苯醚(BDE28、-47、-99、-100、-153、-154、-183)和十溴二苯醚(BDE209)的仪器检出限分别为0.04~0.23 pg和9.38 pg;方法检出限为6.0~27.1 pg/m3和211.6 pg/m3;6点标准曲线相关系数(r)为0.9980~0.9999。方法对8种目标物的加标回收率为79.1%~101.0%,相对标准偏差(RSD)为4.3%~14.3%(n=6)。对6份南京实际大气样品的检测结果表明:离子阱质谱的选择反应监测(selected reaction monitoring,SRM)技术能有效的降低背景干扰。优化后的MS/MS方法对目标化合物有较高的灵敏度,可应用于大气中痕量多溴二苯醚的定量检测。     

Determination of polybrominated diphenyl ethers in soil by ultrasonic assisted extraction and gas chromatography mass spectrometry

An analytical method for the determination of polybrominated diphenyl ethers (PBDEs) in soil was developed. Soil samples were placed in small glass columns and PBDEs extracted from soil, with a low volume of ethyl acetate (5 mL, 2× 15 min), assisted by sonication. PBDEs were determined by gas chromatography with electron impact mass spectrometric detection in the selected ion monitoring mode (GC–MS–SIM) and residues were confirmed by their retention times, selected ions and qualifier–target abundance ratios. Recovery studies were performed at 10, 1, 0.1 and 0.05 μg/kg fortification levels, and the recoveries obtained ranged from 81 to 104% with a relative standard deviation between 1 and 9%. The detection limit of the method varied from 2 to 30 pg/g and the quantification limit ranged from 7 to 100 pg/g for the different PBDEs studied. The developed method was linear over the range assayed, 0.01–10 μg/kg with determination coefficients equal or higher than 0.997. The proposed method was used to determine PBDEs levels in soil samples from different areas of Spain and PBDEs were detected in some samples with values ranging from 1.3 to 5.6 μg/kg.     

Feasibility of two multidimensional techniques, heart-cut MDGC and GCxGC, for the separation of PCBs and PBDEs

The feasibility of heart-cut MDGC-ECD and GCxGC-muECD for the separation of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) has been evaluated. Among the different column combinations tested, the best results were obtained when using either a DB-5 type or an HT-8 column as the first dimension combined with a mid-polar stationary phase (50% phenyl) as the second dimension. The co-elutions between the target PCBs and PBDEs in the first dimension were satisfactorily resolved once transferred to the second column. Repeatability and intermediate precision were satisfactory in both systems, considering retention times in both dimensions. Nevertheless, peak area/volume precision was better for heart-cut MDGC since software for the data analysis in the case of GCxGC was still under development. The need for multiple injections of the same extract on the heart-cut MDGC system was the main drawback since the analysis time it increased. GCxGC becomes then a valuable alternative able to achieve the same performance in one injection. However, the GCxGC data analysis is still very time-consuming and needs further development. The applicability of both separation techniques was shown using a human breast milk sample with low concentrations of PCBs (0.2-227 pg/g fresh weight) and PBDEs (1.2-41 pg/g fresh weight).     

QuEChERS结合气相色谱-质谱法快速测定职业工人尿液中多溴联苯醚

建立了QuEChERS前处理结合气相色谱-质谱快速测定职业工人尿液中8种多溴联苯醚同系物的分析方法。尿液样在氯化钠和无水硫酸镁的脱水与盐析作用下以正己烷-丙酮混合液提取,采用C18去除提取液中的杂质,并采用气相色谱-负化学源质谱法在选择离子监测模式下测定,内标法定量。三至七溴联苯醚在1~100 pg/μL(十溴联苯醚为10~1 000 pg/μL)范围内线性关系良好,相关系数均大于0.999。待测物在3个加标水平下的平均回收率为91.7%~110.2%,相对标准偏差(RSD)小于10%。多溴联苯醚的检出限为0.3~36 pg/m L。该方法简单快速,灵敏度和选择性较高,适合职业工人体内污染物暴露水平监测。     

Imprinted sol-gel electrochemical sensor for the determination of benzylpenicillin based on Fe3O4@SiO2/multi-walled carbon nanotubes-chitosans nanocomposite film modified carbon electrode

In this work, we developed a novel graphene-assisted matrix solid-phase dispersion (GA-MSPD) method for extraction of polybrominated diphenyl ethers (PBDEs) and their methoxylated (MeO-) and hydroxylated (OH-) analogs from environmental samples. We found that grinding the solid sample with chemically converted graphene (CCG) powder yielded a tight contact and sufficient dispersion of the sample matrix due to the large surface area and flexible nanosheet morphology of CCG. The resultant blend was eluted using a two-step elution strategy: PBDEs and MeO-PBDEs were eluted firstly by hexane/dichloromethane and analyzed by GC-ECD, and then OH-PBDEs were eluted by acetone and determined by LC-ESI-MS/MS. The GA-MSPD conditions were optimized in detail. Better recoveries were obtained with GA-MSPD than with other sorbents (C18 silica, Florisil and carbon nanotubes) and other extraction techniques (Soxhlet and accelerated solvent extraction). Other advantages of GA-MSPD, including reduced consumption of sorbent and solvent, good selectivity and short extraction time, were also demonstrated. In analysis of soil samples, the method detection limits of five PBDEs, ten MeO-PBDEs and ten OH-PBDEs were in the range of 5.9-28.7, 14.3-46.6, and 5.3-212.6 pg g(-1) dry weight, respectively. The proposed method was successfully applied to the extraction of PBDEs, MeO-PBDEs and OH-PBDEs from different kinds of spiked environmental samples, including soil, tree bark and fish.     

Analytical performance of a triple quadrupole mass spectrometer compared to a high resolution mass spectrometer for the analysis of polybrominated diphenyl ethers in fish

Polybrominated diphenyl ethers (PBDEs) are a class of flame retardants used globally in many consumer products and industrial applications. Traditionally, gas chromatography–high resolution mass spectrometry (GC–HR-MS) is the method of choice for analysis of PBDEs in environmental samples because it offers high sensitivity and selectivity, resulting in less interferences. However, the specificity offered by gas chromatography-triple quadrupole tandem mass spectrometry (GC–QQQ-MS/MS), operated in selected reaction monitoring mode, provides a more affordable alternative to GC–HR-MS for the analysis of PBDEs in complex environmental samples. In this study, an analytical method was developed for the analysis of 41 PBDE congeners in fish using GC–QQQ-MS/MS. Results from the analysis of three fish species [lake trout (Salvelinus namaycush), yellow perch (Perca flavescens), and round goby (Neogobius melanostomus)] using GC–QQQ-MS/MS were compared with those obtained by GC–HR-MS. These species were selected because they represent varying levels of lipid-rich matrix and contaminant loads. Instrumental limits of detection for the GC–QQQ-MS/MS ranged from 0.04 pg to 41 pg, whereas those for the GC–HR-MS ranged from 5 pg to 85 pg. The PBDE values obtained from these two methods were highly correlated, R² values >0.7, for all three fish species, supporting the suitability of GC–QQQ-MS/MS for analysis of PBDEs in fish with varying fat content.     

Determination of Polybrominated Diphenyl Ethers in Coastal and River Sediments by Pressurized Liquid Extraction Coupled with Gas Chromatography‐Mass Spectrometry

This study presents a time‐ and solvent‐saving method, pressurized liquid extraction (PLE), to extract polybrominated diphenyl ethers (PBDEs) in sediment samples. The effects of various operating parameters (i.e., extraction solution, temperature, pressure, static/dynamic extraction times) for the quantitative extraction of PBDEs by home‐made PLE were systematically investigated and optimized. The analytes were then identified and quantitated by gas chromatography‐mass spectrometry (GC‐MS) in selected ion monitoring (SIM) mode. The 16 PBDE congeners (from tri‐ to deca‐BDE) can be completely extracted by dichloromethane: n‐hexane (3/2, v/v) at 100 °C and 100 atm combined with 15 min static and then 15 min dynamic extraction steps. Recovery of PBDEs in spiked sediment samples ranged from 52 to 104% with 2‐16% RSD, except for BDE‐206. Limits of quantitation (LOQ) were established between 4 and 400 pg/g (dry weight) in 10 g of sediment sample. The extraction efficiency of the PLE was also compared with the traditional Soxhlet extraction method. The total contents of PBDEs ranged from 8.0 to 37.9 ng/g (dry weight) in various river and coastal sediment samples in Taiwan. Deca‐BDE (BDE‐209) was the major PBDE detected in these sediment samples.