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1.
Summary Using a two-step liquid chromatographic separation on normalphase cartridges, crude extracts of diesel particulate matter can be separated without time-consuming sample handling into special fractions which mainly contain slightly-polar oxygenated polycyclic aromatic hydrocarbons (oxy-PAH) and nitrated polycyclic aromatic hydrocarbons (nitro-PAH). Subsequent analysis was by fused-silica capillary gas chromatography on a SE54 column along with flame-ionisation (GC/FID) and positive-ion electron-impact mass spectrometric detection (GC/MS) respectively. A number of individual oxy-PAH belonging to four different chemical classes (ketones, quinones, anhydrides and aldehydes) and several individual nitro-PAH were characterized by their retention times and mass spectra. Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984  相似文献   

2.
气质联用仪法测定奶粉中多环芳烃   总被引:4,自引:0,他引:4  
研究了奶粉中多环芳烃的气相色谱/质谱(GC/MS)测定方法. 样品经甲醇-KOH皂化后用甲苯提取, 提取液经微孔滤膜过滤后用气相色谱质谱仪测定其含量, 外标法定量. 结果16种PAHs的回收率范围为92.0%~106%;RSD为2.2%~4.7%. 方法能同时分离16种PAHs, 适合于奶粉中多环芳烃的分析测定.  相似文献   

3.
A multiresidue method was developed for the de termination of 16 polycyclic aromatic hydrocarbons (PAHs) in unifloral and multifloral honeys. The analytical procedure is based on the matrix solid-phase dispersion of honey on a mixture of Florisil and anhydrous sodium sulfate in small glass columns and extraction with hexane-ethyl acetate (90 + 10, v/v) with assisted sonication. The PAH residues are determined by gas chromatography with mass spectrometric detection using selected-ion monitoring. Average recoveries for all the PAHs studied were in the range of almost 80 to 101%, with relative standard deviations of 6 to 15%. The limits of detection ranged from 0.04 to 2.9 microg/kg. The simultaneous extraction and cleanup of samples makes this method simple and rapid, with low consumption of organic solvents  相似文献   

4.
A novel simplified sample preparation method for quantitative analysis of polycyclic aromatic hydrocarbons (PAH) in water samples by gas chromatography/mass spectrometry (GC/MS) was proposed. The method requires just 1 mL of water and 1 mL of dichloromethane. The detection limits of PAH with the use of high resolution GC/MS are about 1 μg/Λ, while the limits of quantification—10 μg/L. These limits correspond to those for the standard 8270 method of the United States Environmental Protection Agency.  相似文献   

5.
6.
建立了气相色谱-三重四极杆串联质谱检测环境空气中多环芳烃的方法,并利用同位素稀释法对多环芳烃进行了测定。将该方法应用于华南地区某大型石化企业周边环境空气中多环芳烃的检测,并与气相色谱-质谱方法进行了对比。结果表明,该方法的仪器检出限(0.01~0.15 μg/L)和定量限(0.03~1.5 μg/L)均优于气相色谱-质谱法(0.1~0.8 μg/L和0.3~3.5 μg/L),并有更好的灵敏度与选择性。当利用气相色谱-质谱作为检测手段时,回收率指示物氘代菲和进样内标六甲基苯均受到了杂质的严重干扰,影响了定量结果的准确性,而三重四极杆串联质谱很好地解决了这些问题。实际样品分析时,标准曲线中16种多环芳烃相对响应因子的相对标准偏差为2.60%~15.6%,氘代化合物的回收率为55.2%~82.3%,空白加标样品的回收率为98.9%~111%,平行样品的相对标准偏差为6.50%~18.4%,采样空白含量范围为未检出~44.3 pg/m3,实验室空白含量范围为未检出~36.5 pg/m3。上述研究表明,分析环境空气中的多环芳烃时,气相色谱-三重四极杆串联质谱方法值得推广。  相似文献   

7.
Polycyclic aromatic hydrocarbons (PAH) from ambient air particulate matter (PM) were analyzed by a new method that utilized direct immersion (DI) and cold fiber (CF) SPME-GC/MS. Experimental design was used to optimize the conditions of extraction by DI-CF-SPME with a 100μm polydimethylsiloxane (PDMS) fiber. The optimal conditions included a 5min equilibration at 70°C time in an ultrasonic bath with an extraction time of 60min. The optimized method was validated by the analysis of a NIST standard reference material (SRM), 1649b urban dust. The results obtained were in good agreement with certified values. PAH recoveries for reference materials were between 88 and 98%, with a relative standard deviation ranging from 5 to 17%. Detection limits (LOD) varied from 0.02 to 1.16ng and the quantification limits (LOQ) varied from 0.05 to 3.86ng. The optimized and validated method was applied to the determination of PAH from real particulate matter (PM10) and total suspended particulate (TPS) samples collected on quartz fiber filters with high volume samplers.  相似文献   

8.
An accurate, precise and sensitive method is described for the analysis of 29 polycyclic aromatic hydrocarbons (PAHs), including 19 2-6-ringed PAHs and 10 alkyl-PAHs. The method is based on an isotope dilution technique using gas chromatography/mass spectrometry (GC/MS) and available labeled PAHs as internal standards. Quality parameters were calculated with satisfactory results and 36 Spanish river sediments were analysed. Results were evaluated regarding to the sediment quality guidelines (SQGs) based on the effects range-low (ERL) and the effects range-median (ERM) values. Most analysed sediments showed a good quality, since only 7 of them exceeded ERL values, including one sample surpassing ERM values. PAH profiles were studied in order to identify PAH sources as mainly petrogenic or pyrogenic. Most samples showed petrogenic-type fingerprints, although 6 of the 11 sediments with the highest PAH concentrations (> 1000 ng/g) were classified as pyrogenic, including 4 of the 7 samples exceeding ERL values. Quality assurance was carried out by the triplicate analysis of one preanalysed river sediment without PAHs subsequently spiked at a medium (500 ng/g) and a low concentration level (10 ng/g) of each analyte. Main quality requirements for methods based on isotope dilution were accomplished. Method accuracy was 80-120% for most PAHs, method precision was <15% for all the analysed compounds and method detection limits (MDLs) were 1-3 ng/g.  相似文献   

9.
Polynuclear aromatic hydrocarbons (PAH) and their nitrogen analogs, basic azaarenes, are extracted from samples of airborne particulate matter by toluene with ultrasonic treatment. The basic azaarenes are extracted from the toluene phase with phosphoric acid, re-extracted from the phosphoric acid phase (adjusted to pH 14 with potassium hydroxide) with dichloromethane, and determined by capillary gas chromatography (g.c.) with a nitrogen-sensitive detector. The PAH in the toluene phase are isolated by means of semipreparative high-performance liquid chromatography and liquid-liquid extraction and determined by g.c. with a flame-ionization detector. Eleven basic azaarenes were identified; their concentration were one to two orders of magnitude lower than those of PAH. Results from the determination of the concentrations of basic azaarenes and PAH in the atmosphere in a busy street and in a suburban residential area of Copenhagen are presented and discussed.  相似文献   

10.
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...  相似文献   

11.
Polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nitro-PAH) are environmental pollutants which pose a threat to human health even at low concentration levels. In this study, efficient analytical methods for the analysis of nitro-PAH and PAH (extraction, clean-up, chromatographic separation, and spectrometric detection) have been developed, characterized, and applied to aerosol samples. The separation and quantification of 12 nitro-PAH was carried out by reversed-phase high performance liquid chromatography (HPLC), on-line reduction, and fluorescence detection. The detection limits were in the range of 0.03–0.5 g L–1 (6–100 pg in the investigated sample aliquots), and the recovery rates from soot samples were 70–90%. Nitro-PAH and PAH concentrations have been determined for different types of soot and for urban, rural, and alpine fine air particulate matter (PM2.5). For the first time, trace amounts of nitro-PAH have been detected in a high-alpine clean air environment. The on-line reduction and fluorescence technique has been complemented by atmospheric pressure chemical ionization time-of-flight mass spectrometry (APCI-TOF-MS). The MS detection allowed the analysis of partially nitrated and oxygenated PAH in laboratory studies of the heterogeneous reaction of PAH on soot and glass fiber substrates with gaseous nitrogen oxides and ozone. It led to the tentative identification of a previously unknown nitrated derivative of the particularly toxic PAH benzo[a]pyrene (BaP-nitroquinone), and provides the first experimental evidence that PAH-nitroquinones can be formed by reaction of PAH with atmospheric photooxidants.  相似文献   

12.
Summary Since the carcinogenic effect of emissions from hard coal briquet-fired furnaces is almost entirely caused by polycyclic aromatic compounds (PAC) with more than three rings, the composition of this fraction has been analyzed in detail.More than 170 neutral [111 polycyclic aromatic hydrocarbons (PAH), 57 thiaarenes, 6 oxaarenes] and 70 basic (azaarenes) compounds were characterized as PAC by means of GC/MS (limit of detection 0.1 mg/kg briquet). About 80 compounds were identified by comparison with reference standards. In order to obtain unequivocal evidence for the identification of 11 PAH with a molecular weight of 302, the UV- and fluorescence spectra were compared with those of the synthesized reference compounds [naphtho(1,2-k) fluoranthene, dibenz(e,k)acephenanthrylene, naphth-(2,3e) acephenanthrylene, naphtho(2,3-k)fluoranthene, dibenzo (de,qr)naphthacene, coronene, dibenzo(fg,op)naphthacene, naphtho(1,2,3,4-def)chrysene, benzo(b)perylene, dibenzo (-def,j)chrysene, benzo(rst)pentaphene]. In case of the emission condensate from hard coal briquets, PAC containing 6 and more rings cause about 50% of the carcinogenic effect in animal experiments.
Bestimmung von polycyclischen aromatischen Kohlenwasserstoffen, Azaarenen und Thiaarenen in der Emission von Kohle-beheizten Haushaltöfen — Bestandsaufnahme durch GC/MS
Zusammenfassung Da die krebserzeugende Wirkung von Emissionen aus Steinkohlebrikett-beheizten Zimmeröfen nahezu vollständig durch die im Kondensat enthaltenene polycyclischen aromatischen Verbindungen (PAC) mit mehr als 3 Ringen verursacht wird, wurde die Zusammensetzung dieser PAC-Fraktion untersucht.Mehr als 170 neutrale [111 polycyclische aromatische Kohlenwasserstoffe (PAH), 57 Thiaarene, 6 Oxaarene] sowie 70 basische Verbindungen (Azaarene) konnten mit der GC/MS-Kombination als PAC charakterisiert werden (Nachweisgrenze 0,1 mg/kg Brikett). Etwa 80 Verbindungen wurden durch den Vergleich mit Referenzsubstanzen identifiziert. Um in einigen zweifelhaften Fällen die Identität der isolierten mit der synthetischen Verbindung zu bestätigen, wurden bei 11 PAH mit einem Molgewicht von 302 zusätzlich auch UV- und Fluorescenzspektren verglichen [Naphtho(1,2-k)fluoranthen, Dibenz(e,k)acephenanthrylen, Naphth(2,3-e)acephenanthrylen, Naphtho(2,3-k)fluoranthen, Dibenzo(de,qr)naphthacen, Coronen, Dibenzo(fg,op)naphthacen, Naphtho(1,2,3,4-def)chrysen, Benzo(b)perylen, Dibenzo(def,j)chrysen, Benzo(rst)pentaphen]. Diese Verbindungen sind von besonderem Interesse, da PAC mit 6 und mehr Ringen im Tierversuch etwa 50% der carcinogenen Wirkung des Steinkohlenbrikett-Emissionskondensates verursachen.
  相似文献   

13.
14.
刘洪媛  金静  郭崔崔  陈吉平  胡春 《色谱》2022,40(7):644-652
环境空气中的多氯萘(PCNs)一般为痕量水平(pg/m^(3)),要实现其准确定量必然对分析方法的提取、净化和仪器分析提出较高要求。研究通过考察提取溶剂种类、净化流程和色谱-质谱参数,建立了加速溶剂萃取(ASE)-多层硅胶复合中性氧化铝柱的净化方法,并利用同位素稀释气相色谱-三重四极杆质谱(GC-MS/MS)对环境空气中的多氯萘进行测定。同时,通过在采样、提取和进样分析前分别添加同位素内标,开展质量控制和保证。结果表明,在2~100 ng/mL范围内3~8氯萘的平均相对响应因子(RRF)的相对标准偏差(RSD)均小于16%。PCNs同类物的方法检出限为1~3 pg/m^(3)(以样品体积为288 m^(3)计算)。采用基质加标法评价了方法对环境空气样品中PCNs测定的精密度和准确度,低、中、高加标水平下3~8氯萘的平均加标回收率分别为89.0%~119.4%、98.6%~122.5%和93.7%~124.5%,测定结果的平均相对标准偏差分别为1.9%~7.0%、1.6%~6.6%和1.0%~4.8%。整个分析过程中,采样内标和提取内标的平均回收率分别为136.2%~146.0%和42.4%~78.1%,RSD分别为5.6%~7.5%和2.7%~17.5%,满足痕量分析的要求且平行性较好。方法的灵敏度和准确度高,精密度良好,适用于环境空气中3~8氯萘的准确定量测定,可在一定程度上缓解多氯萘监测对高分辨气相色谱-高分辨质谱的依赖,为实现多氯萘的国际履约提供方法支持。  相似文献   

15.
An equation is theoretically derived which describes the relative standard deviation (RSD) of the amount ratios of analyte to its isotope-labeled variant in gas chromatography/mass spectrometry (GC/MS) using the stable isotope dilution method. The determination of methyltestosterone is taken as an example. The uncertainty equation proposed is justified by comparing the theoretical RSD values with the experimental RSD values obtained by replication over a wide range of analyte amount. The detection limit and quantitation limit are estimated from the continuous plot (precision profile) of the theoretical RSD against analyte amount.  相似文献   

16.
Müller J  Rohbock E 《Talanta》1980,27(8):673-675
A method for measuring polycyclic aromatic hydrocarbons (PAHs) in ambient air is described. The particulate matter is collected on fibre-glass filters. The loaded filters are placed in tetrahydrofuran and the PAHs dissolved with the aid of ultrasonics and analysed by high-performance liquid chromatography on a reversed-phase column with a methanol-water mixture as mobile phase. The PAHs are detected by use of a UV-detector and the 254-nm mercury emission line. The method is rapid and adequate for measuring about 15 PAH-components in ambient air.  相似文献   

17.
An automated, simple, and reproducible method was developed for the determination of benzene in soft drinks, based on isotope dilution headspace gas chromatography/mass spectrometry in the selected-ion monitoring mode. The method was used to assess benzene levels in samples of 124 soft drinks and beverages. Benzene was not detected in 60% of the 124 products. The average benzene levels in 6 products exceeded the Canadian maximum acceptable concentration of 5 microg/L for benzene in drinking water, and 2 of the 6 products had benzene levels above the World Health Organization guideline of 10 microg/L. The highest level of benzene, 23 microg/L, was found in a soft drink product specifically marketed to children.  相似文献   

18.
Summary Polycyclic aromatic hydrocarbons (PAHs) were determined in atmospheric particulate matter in 11 sites of the Valencia area and at several times during the year. Sample analysis was carried out by ultrasonic acetonitrile extraction followed by reverse phase HPLC separation and fluorescence detection. The maximum concentration of total PAH developed in winter and spring. Mean values per sampling site varied from 0.193 to 1.668 g/m3 of filtered air. Environmental noise and temperature were determined at those same 11 sites and correlated with PAH levels.  相似文献   

19.
Thirteen polycyclic aromatic hydrocarbons have been determined in soy‐based nutraceutical products. First, an optimization of extraction procedure was performed, and a solid–liquid extraction assisted by sonication and a dilute and shoot procedure were compared, selecting the dilute and shoot approach for the extraction of target compounds, utilizing a mixture of acetone/n‐hexane (1:1 v/v) as extractant solvent. After this, a clean‐up step was needed bearing in mind the complexity of these matrices. Dispersive solid‐phase extraction, using a mixture of C18 and Zr‐Sep+ (25 mg/mL each) was used. The separation was achieved by gas chromatography and detection with triple quadrupole tandem mass spectrometry. For quantification purposes, matrix‐matched calibration was used. The validation was applied at three concentration levels (20, 100 and 250 μg/kg), obtaining recoveries between 70 and 120% and precision values equal to or lower than 23%. Limits of detection and quantification were below 8 and 20 μg/kg, respectively. The method was applied in 11 samples, detecting five polycyclic aromatic hydrocarbons at concentrations ranging from 4.1 to 18.5 μg/kg.  相似文献   

20.
张静星  郑晓燕  谭丽  刘进斌  于海斌 《色谱》2021,39(5):541-551
建立了测定大气中25种有机氯农药(OCPs)的同位素稀释-高分辨气相色谱/高分辨质谱法(ID-HRGC/HRMS).样品用正己烷/二氯甲烷(1:1,v/v)进行加速溶剂萃取(ASE).通过柱洗脱实验、单柱和组合柱净化实验,最终确定样品的净化方案为弗罗里硅土固相萃取柱和石墨化炭黑固相萃取柱组合净化.样品萃取液净化后进行H...  相似文献   

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