手性气相色谱质谱法测定莲藕及底泥中的多氯联苯对映体

采用气相色谱质谱（GC MS）建立了莲藕、荷叶、荷茎及池塘底泥中6种手性多氯联苯（PCBs）PCB 91,95,136,149,176和183的分离分析方法。优化了对映体的仪器分离检测条件,考察了前处理中加速溶剂萃取（ASE）参数、提取剂以及净化方式等对方法的影响,最终确定采用正己烷丙酮（1:1,V/V）在萃取温度100℃、压力10.3 MPa下静态提取10 min,提取液经H₂SO₄磺化后过Florisil小柱净化,洗脱液经浓缩并用异辛烷定容后,用分别配有Chirasil Dex和BGB-172手性毛细管色谱柱的GC-MS检测。6种手性PCBs对映体的线性范围为0.5～100μg/L,在0.25,2.5和25μg/kg添加浓度的回收率为82.8%～11 7.0%,相对标准偏差（RSD）为1.5%～13.6%,检出限为0.01～0.02μg/kg,定量限为0.025～0.04μg/kg。将本方法应用于实际样品的测定,在市售莲藕未检出6种手性PCBs,而污染区的莲藕、荷茎、荷叶及其生长底泥中均含有较高浓度手性PCBs,并且莲藕、荷茎和荷叶中PCB 91-2,PCB 95-1和（+）PCB 136的浓度均高于其对映体,而PCB 149,1 76和1 83的两个对映体之间均无显著的浓度差异。     

牡蛎中痕量有机氯农药残留量的分析方法研究

建立了同时测定牡蛎中16种有机氯农药残留量的前处理方法和气相色谱分析方法。在100℃的温度条件下，用加速溶剂提取（ASE）提取样品中的有机氯农药，用凝胶渗透色谱（GPC）结合Florisil柱净化，以RTX-5MS毛细管色谱柱分离、ECD检测器测定。结果表明，样品的加标回收率（n=3）为81％～110％，方法检出限为0．2～0．7ng／g，样品检测的相对标准偏差为2．9％～15．2％。     

加速溶剂萃取-气相色谱串联质谱法检测沉积物中痕量增塑剂

研究了加速溶剂萃取(ASE)对沉积物中邻苯二甲酸酯类(PAEs)物质的提取效果,建立了快速溶剂萃取/气相色谱-质谱联用(GC/MS)检测沉积物中16种邻苯二甲酸酯类物质的方法。用正己烷和二氯甲烷混合溶剂作为提取溶剂,加速溶剂萃取法萃取沉积物中16种PAEs,再用Florisil层析柱净化,最后用GC/MS对净化后提取液中的PAEs进行定量分析。结果表明:当萃取剂为二氯甲烷-正己烷(1∶1,V/V),萃取温度为80℃时,萃取效率最高,16种PAEs的回收率稳定在81.2%～128.5%之间,相关系数≥0.99,检出限为0.12～0.98 ng/g,相对标准偏差为1.1%～10.8%。加速溶剂萃取法与传统索氏提取法相比,既提高了萃取效率同时又减少了有机萃取溶剂的用量。在检测实际样品时,同时加入3种内标指示剂对方法的性能进行了验证,3种内标的回收率分别为106.0%±18.8%,87.4%±10.8%和81.4%±14.5%,样品中16种PAEs的检出率为100%。前处理方法处理简单,定性与定量分析准确可靠。     

大豆中二硝基苯胺类除草剂多残留的气相色谱法定量检测及质谱确证

建立以凝胶渗透色谱法（GPC）和固相萃取法（SPE）及气相色谱法（GC）联用技术测定大豆中10种二硝基苯胺类除草剂（氟乐灵、乙氟灵、环丙氟、氯乙氟灵、仲丁灵、异乐灵、二甲戊乐灵、二硝胺、氨基丙氟灵和磺乐灵）多残留检测方法。目标农药经正己烷饱和的乙腈提取，凝胶渗透色谱除去大豆中大部分油脂及色素，再经Florisil柱净化和富集，依次用6mL二氯甲烷和6mL二氯甲烷＋丙酮（99＋1）洗脱。目标农药采用电子捕获检测（GC／ECD），外标法定量，并经质谱（MS）确证。两个添加水平重复6次，回收率分别为74％～105％和59％～105％；相对标准偏差〈20％；检出限为1．8～7．6μg／kg；定量限为6～38μg/kg。     

土壤中10种多溴联苯醚的加速溶剂-固相萃取净化方法优化研究

建立了土壤中10种多溴联苯醚(PBDEs)的加速溶剂萃取-固相萃取净化-气相色谱分析测定方法.采用加速溶剂萃取(ASE)技术对土壤中10种PBDEs进行提取,并对4种萃取体系(正己烷、正己烷-丙酮(4∶1,V/V)、正己烷-丙酮(1∶1,V/V)、正己烷-二氯甲烷(1∶1,V/V))进行优化;采用固相萃取(SPE)技术对样品进行净化,制备了10种不同填料的SPE柱,通过洗脱实验和加标回收率实验对各SPE柱的净化性能进行对比筛选.最终优化条件为正己烷-丙酮(4∶1,V/V)体系提取,酸性硅胶柱净化.在优化条件下,10种PBDEs的回收率为74.4％ ～ 125.2％,相对标准偏差为4.4％ ～ 14.4％,方法检出限为0.04～0.22 ng/mL.本方法简单、快速、净化效果较好、重现性和回收率良好,可用于土壤样品中PBDEs的分析.     

鱼肉样品中的手性多氯联苯对映体的分离测定研究

该文建立了鱼肉样品中7种手性多氯联苯(PCB 45,PCB 91,PCB 95,PCB132,PCB 136,PCB 149和PCB 174)对映体的分离测定方法。样品经快速溶剂萃取技术萃取后,浓缩液经过凝胶渗透色谱除脂及大分子物质后再依次通过酸性硅胶柱、复合硅胶柱净化和碱性氧化铝柱分离得到PCBs组分。在气相色谱-质谱(GC-EI/MS)上对比研究了Bate Dex-325,CP-Chirasil,BGB-172SE,Chirasil-Dex和Cyclosil-B手性色谱柱的拆分效果,发现7种手性PCBs在Cyclosil-B毛细管柱上的分离效果最好,其分离度为0.8~2.3,可以实现基线分离。在优化色谱条件下,7种手性PCBs在10~200μg·L-1浓度范围内线性良好,相关系数为0.998~1.000,方法检出限(S/N=3)为0.4~5.0 ng·g-1。在高、低2个加标水平下,7种手性PCBs的回收率为89.2%~114%,相对标准偏差为0.3%~2.1%,表明方法灵敏度高、回收率好、准确度高。采集广东电子垃圾拆解污染区鱼类样品验证方法的适用性,结果显示鱼肉样品中均检出7种手性PCBs,3种鱼肉样品中7种手性PCBs的总浓度为386.7~602.8 ng·g-1。对3种鱼肉组织中7种手性PCBs的EF值进行测定,发现PCB 45,PCB 91,PCB 95,PCB 132,PCB 136和PCB 174的EF值与标准品具有显著差异,表明这些手性PCBs在鱼类体内可能具有对映体选择性富集和代谢作用,此外PCB 45,PCB 91,PCB 95,PCB 132和PCB136在3种鱼肉组织中的分布特征相似,而PCB174的EF值在乌鳢体内大于标准品,而在鲮鱼、鲫鱼体内却小于标准品,表明PCB174在乌鳢和鲮鱼、鲫鱼体内的选择性代谢过程可能相反。     

气相色谱/高分辨质谱联用测定环境样品中的二噁英和类二噁英多氯联苯

样品采用索氏抽提,抽提液依次经酸性硅胶床、多段混合硅胶柱和凝胶渗透色谱柱(GPC)净化后,用Florisil硅藻土柱分离出样品中的二噁英(PCDD/Fs)和类二噁英多氯联苯(dioxin-like PCBs),采用同位素稀释法和气相色谱/高分辨质谱联用仪(GC/HRMS)测定了其中的17个2,3,7,8-氯取代二噁英类化合物和12个类二噁英多氯联苯。结果表明,用该法分析二噁英和多氯联苯标准溶液,平行4次的分析结果为:RSD(PCDD/Fs)<8.9%,RSD(PCBs)<11.4%;回收率可达60%-105%。PCDD/Fs和PCBs的检出限分别为0.1-0.8 pg/g和0.05-0.6 pg/g。应用本方法成功测定了沉积物、淤泥、土壤和飞灰中的二噁英和类二噁英多氯联苯,并计算出它们的毒性当量。     

加速溶剂萃取法与索氏提取法对废线路板中二噁英测定的影响

将经过多级破碎分选所得的废线路板粉末过60目筛,以2 mol/L HCl溶液、超纯水洗涤,并用丙酮脱水.将预处理后的滤渣、滤纸填入萃取池,或者用新滤纸包裹后置于索氏提取管内,添加5 μL内标物,分别用加速溶剂萃取法(ASE)或索氏提取(SE)法进行萃取,依次采用多层硅胶柱和活性炭柱对萃取提取物进行净化、洗脱,得到二噁英测试样品.用同位素稀释-高分辨气相色谱-质谱联用仪分析样品中二噁英的含量.考察两种提取方法及不同氯代数对15种13C-2,3,7,8-PCDD/Fs回收率的影响,比较两种方法的准确度和精密度.结果表明,ASE和SE对15种13C-2,3,7,8-PCDD/Fs的回收率分别为54.3%~113.0%和28.3%~77.7%, 实测废线路板中二噁英毒性当量(Toxic equivalent quangtity,TEQ)分别为0.075 ng TEQ/kg和0.266 ng TEQ/kg.在方法精密度允许范围内,ASE相对具有简单快速、溶剂用量少和准确的优势.     

同位素稀释三重串联四级杆质谱法测定鱼组织中24种多环芳烃

采用气相色谱-三重串联四级杆质谱联用技术测定了鱼组织中24种多环芳烃(PAHs).将冻干鱼组织样品加入同位素内标后,用加速溶剂萃取法(ASE)进行提取,提取液采用凝胶排阻色谱(GPC)和固相萃取(SPE)联用进行净化.采用二氯甲烷为提取溶剂,100℃下提取,以二氯甲烷作为GPC的流动相,在3.5 mL/min流速下,收...     

ASE-HPLC检测某型号球形发射药中的叠氮硝胺、硝化甘油、Ⅱ号中定剂含量的研究

采用快速溶剂萃取（ASE）技术和高效液相色谱法测定某球形药中叠氮硝胺（DIANP）、硝化甘油（NG）和Ⅱ号中定剂（C2）的含量．ASE提取条件：二氯甲烷做萃取溶剂,萃取温度100℃,静态萃取10min,萃取2次．HPLC测定条件：YWGC18柱（150×4．6mm,10μm）,以甲醇和水作为流动相,梯度洗脱,流速1 mL／min,检测波长210nm．测定结果表明DIANP、NG、C2平均回收率分别为99．6％、100．3％、99．4％,RSD分别为0．7％、0．8％、0．9％（n=5）,检出限分别为2.1、1.5和0．2mg／L,线性范围分别为0．02～0．98g／L,0．03～1．38g／L,0．002～0．124g／L．用此方法共检测某批球形发射药样品5份,检测结果与滴析-HPLC法检测结果相当．     

Evaluation of Soxhlet extraction, accelerated solvent extraction and microwave-assisted extraction for the determination of polychlorinated biphenyls and polybrominated diphenyl ethers in soil and fish samples

Three commonly applied extraction techniques for persistent organic chemicals, Soxhlet extraction (SE), accelerated solvent extraction (ASE) and microwave-assisted extraction (MAE), were applied on soil and fish samples in order to evaluate their performances. For both PCBs and PBDEs, the two more recent developed techniques (ASE and MAE) were in general capable of producing comparable extraction results as the classical SE, and even higher extraction recoveries were obtained for some PCB congeners with large octanol-water partitioning coefficients (K_ow). This relatively uniform extraction results from ASE and MAE indicated that elevated temperature and pressure are favorable to the efficient extraction of PCBs from the solid matrices. For PBDEs, difference between the results from MAE and ASE (or SE) suggests that the MAE extraction condition needs to be carefully optimized according to the characteristics of the matrix and analyte to avoid degradation of higher brominated BDE congeners and improve the extraction yields.     

土壤与沉积物样品中多氯联苯总量的气相色谱-质谱法快速分析

建立了土壤和沉积物样品中多氯联苯总量的快速分析方法.样品经加速溶剂萃取,Bond ElutPCB SPE小柱净化后,采用气相色谱-质谱测定多氯联苯的总量,方法的平均回收率为84% ～106%,相对标准偏差为4.2% ～8.4%,多氯联苯总量的方法检出限为2.25 ng/g.该方法快速、灵敏、准确,适用于大部分土壤及沉积物样品中多氯联苯总量的快速筛查分析.     

分散固相萃取-超高压液相色谱-串联质谱法测定茶叶中赤霉酸和α-萘乙酸

建立了分散固相萃取-超高压液相色谱-串联质谱分析茶叶中两种植物激素赤霉酸(GA3)与α-萘乙酸(NAA)含量的方法。样品经甲醇均质提取,采用弗罗里硅土、石墨化炭黑(GCB)、丙基乙二胺(PSA)和C18混合吸附剂分散萃取净化。采用HSS C18色谱柱(100mm×2.0mm,1.8μm),电喷雾电离(-),多反应监测模式扫描(MRM),UPLC-ESI(-)-MS/MS检测,外标法定量分析。GA3和NAA分别在0.05～5.0mg/kg与0.10～5.0mg/kg范围内线性关系良好,相关系数r≥0.9990,定量限分别为0.05与0.10mg/kg。GA3和NAA在0.1,0.5和1.0mg/kg水平上的添加回收率分别在85.0%～86.8%和82.9%～84.4%之间,精密度(RSD)≤4.5%。本方法操作简单、准确,适用于测定茶叶中GA3和NAA残留量。     

固相萃取-GC-MS法测定水中四氯联苯

建立全自动固相萃取-气相色谱-质谱法检测水中微量四氯联苯的方法。采用全自动固相萃取装置配有C_(18)固相萃取盘富集浓缩水中四氯联苯后,用乙酸乙酯和二氯甲烷洗脱,以CD-5MS毛细管色谱柱分离,气相色谱质谱法测定水中四氯联苯的含量。对水样的洗脱剂、萃取流速、pH值、甲醇加入量等进行了优化试验,四氯联苯PCB52,PCB77,PCB81的质量浓度在5.00~50.0μg/L范围内与色谱峰面积呈良好的线性,检出限分别为0.002,0.003,0.002μg/L;加标回收率分别为90.9%,92.7%,95.4%;测定结果的相对标准偏差均小于3%(n=7)。该方法灵敏度高,适用于水样中痕量四氯联苯的监测。     

Assisted solvent extraction and ion-trap tandem mass spectrometry for the determination of polychlorinated biphenyls in mussels. Comparison with other extraction techniques

A selective and sensitive analytical method for determination of ten congeners of polychlorinated biphenyls (PCBs 31, 28, 52, 101, 118, 153, 105, 138, 156, and 180) in mussel samples (Mytilus galloprovincialis) based on accelerated solvent extraction (ASE) and gas chromatography–tandem mass spectrometry (GC–MS–MS) is presented in this work. Extraction conditions were optimised using a Plackett–Burman factorial design. The final extracts were analysed after cleanup on alumina columns. The optimised extraction parameters were solvent percentage, sample amount, extraction temperature, pressure, static extraction time, flush percentage, and purge time. The results suggest that PCBs 118, 105, and 180 extractions appeared affected by only one statistically significant factor, pressure, solvent percentage and static extraction time, respectively. Extraction of PCBs 138 and 156 was affected by amount of sample. PCB 138 extraction was also statistically affected by static extraction time and purge time. Quantitative recoveries (64.8–120.3%) were achieved for all PCBs and method precision (RSD < 19%) was satisfactory.     

The dependence of sorbent/analyte type on observed differences in supercritical fluid extraction efficiencies employing extraction vessels of different dimensions

Summary The effect of extraction cell dimensions (i.d.: length) on supercritical fluid extraction (SFE) efficiencies of polychlorinated biphenyls (PCBs) is shown to be dependent on the type of sorbent used. For octadecylsilane (C18) sorbents, there is a significant increase in observed SFE recoveries of PCBs when the cell dimensions are made more broad (increased i.d.: length); whereas, no effect of cell geometry is observed when the common adsorbent, Florisil, is utilized. Additionally, recoveries decreased in proportion to the chlorine number, for the PCBs studied, for octadecylsilane sorbents, while no such effect was observed for Florisil. These results illustrate the magnitude of the matrix effect in SFE, which generally dominated observed recoveries, even in the simplest analyte/sorbent systems such as the one studied here.     

加速溶剂萃取同步净化-同位素内标-气相色谱-高分辨质谱测定水产品中32种多氯联苯

建立了加速溶剂萃取同步净化-同位素内标-气相色谱-高分辨质谱同时测定水产品中32种多氯联苯含量的方法。通过在加速溶剂萃取仪中加入2 g无水硫酸钠、1 g弗罗里硅土、50 g中性氧化铝作为吸附剂实现同步净化的效果，萃取溶剂为二氯甲烷-正己烷（1:1，v/v），萃取温度为100℃，循环2次。萃取结束后分别用0.5 mL浓硫酸净化两次，净化液浓缩定容后，采用气相色谱-高分辨质谱测定，同位素内标法定量。32种多氯联苯在0.1~20 μg/L范围内平均相对响应因子（RRF）的相对标准偏差（RSD）值（n=7）均小于15%，定量限（S/N=10）为0.3~1.9 ng/kg。在草鱼和海鲈鱼空白基质中做加标回收试验，添加水平为5、20和50 ng/kg，得到的平均回收率为71.9%~119.0%（n=6），RSD为3.5%~19.6%。该方法背景干扰低，灵敏度高，重现性好，回收率稳定，适用于水产品中多氯联苯的检测。     

Determination of polychlorinated biphenyls in biota samples using simultaneous pressurized liquid extraction and purification

In order to reduce time and cost of analysis, a new pressurised liquid extraction method that automatically and rapidly achieves quantitative and selective (i.e., lipid-free) extraction of polychlorinated biphenyls (PCBs) in biota tissues was optimized. It consists of on-line clean-up by inclusion of sorbents in the extraction cell. The freeze-dried sample is dispersed with Florisil and loaded in the extraction cell containing an extra amount of Florisil. The extraction is performed under mild conditions using 55 ml of a dichloromethane-pentane (15:85) mixture, a temperature of 40 degrees C, a static extraction time of 10 min and two extraction cycles. The Florisil retains coextracted lipids from the matrix, and the extract, after pre-concentration, is clean enough for direct injection into GC-MS and GC-electron-capture detection (ECD). Quantitative recoveries (from 90 to 106%) are obtained for both native and spiked PCB congeners in samples with a high lipidic content (up to 42% dry mass, in spoonbill eggs). The reproducibility of replicate extractions was better than 11% relative standard deviation. Method detection limits were in the ranges of 0.001-0.004 and 0.002-0.07 ng g(-1) dry mass for GC-ECD and GC-MS-MS, respectively. The method was validated using the standard reference material SRM 2974 (a mussel tissue) from the US National Institute of Standards and Technology, compared to Soxhlet and matrix solid-phase dispersion extraction methods, and used to evaluate the contamination by PCBs in bivalves from South of Spain.     

Chiral comprehensive two-dimensional gas chromatography with electron-capture detection applied to the analysis of chiral polychlorinated biphenyls in food samples

The feasibility of comprehensive two-dimensional gas chromatography with electron-capture detection (GC x GC-ECD) for the enantioseparation of chiral PCBs from other possible interfering compounds has been evaluated. Three commercially available enantioselective beta-cyclodextrin-based capillary columns (Chirasil-Dex, BGB-172 and BGB-176SE) have been tested as first-dimension columns. Three non-enantioselective stationary phases (HT-8, BPX-50 and Supelcowax-10) were combined with the enantioselective columns to allow the unambiguous determination of the enantiomers of the target chiral PCBs. Each enantioselective first-dimension column tested was able to separate into enantiomers different PCB congeners, but in all cases, the use of Supelcowax-10 as second-dimension column provided the most satisfactory results. The Chirasil-Dex x Supelcowax-10 column combination allowed the determination of the enantiomeric fraction (EF) of PCBs 84, 91, 95, 132, 136, 149, 174 and 176 in the working standard solution, while that of congener 135 was hindered. The BGB-172 x Supelcowax-10 column set allowed a proper EF determination of congeners 45, 84, 131, 132, 135, 171, 174 and 183, while that of PCB 91 was interfered with co-elutants. The column combination BGB-176SE x Supelcowax-10 allowed the determination of all congeners that this enantioselective stationary phase was able to separate into enantiomers, i.e. PCBs 45, 91, 95, 136, 149 and 176. These column combinations have also been evaluated for the simultaneous determination of the 12 congeners with a toxic equivalency factor assigned by the WHO (PCBs 77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169, 189) and the seven indicator congeners (PCBs 28, 52, 101, 118, 138, 153 and 180), and evaluated for the analysis of food samples.     

固相萃取-高效液相色谱法测定浓缩苹果汁中的多菌灵残留量

报道了固相萃取-高效液相色谱法测定浓缩苹果汁中多菌灵残留量的方法.样品经适量水稀释后,C18固相萃取柱提取净化,用V(甲醇)∶V(二氯甲烷)=1∶1淋洗,HPLC法测定.在添加水平为0.10,0.50,2.0 mg/kg时,多菌灵的回收率在92.6%～108.3%之间;RSD＜3% (n=6),检出限为0.02 mg/kg,该方法的测定结果满足农药残留量的检测要求.