全自动固相萃取-气相色谱-串联质谱法测定卷烟主流烟气中的3种多环芳烃

以全自动固相萃取技术净化主流烟气萃取液,建立了卷烟主流烟气中苯并［a］芘、苯并［a］蒽和屈艹 3种多环芳烃的气相色谱-串联质谱(GC-MS/MS)测定方法。以吸烟机抽吸卷烟,并以剑桥滤片捕集卷烟主流烟气,然后以含氘代苯并［a］芘内标的环己烷溶液萃取滤片,萃取液经全自动固相萃取仪净化后以GC-MS/MS分离检测。结果表明,苯并［a］芘、苯并［a］蒽和屈艹 的检出限分别为0.05、0.16和0.23 ng/cig,回收率为91.5%～102.1%,相对标准偏差(RSD)均小于5%。该方法的自动化程度高、操作简便、检出限低、重复性好,适用于卷烟主流烟气中苯并［a］芘、苯并［a］蒽 3种多环芳烃释放量的检测。     

Resolution of benzo[a]pyrene in complex mixtures of other polycyclic aromatic hydrocarbons. Comparison of two spectrofluorimetric methods applied to water samples

Two spectrofluorimetric methods, second-derivative constant-energy synchronous luminescence (SDCESL) and constant-wavelength synchronous luminescence (CWSL) in combination with multiple linear regression (MLR), for the quantification of benzo[a]pyrene (BaP) at sub-ng mL-1 levels, in the presence of benzo[b]fluoranthene (BbFt), benzo[k]fluoranthene (BkFt), benzo[ghi]perylene (BghiP) and indeno[1,2,3-cd]pyrene (IP), were developed and compared in detail. SDCESL presents lower limits of detection and quantification than CWSL/MLR and also gives more exact and precise results for levels close to the quantification limit. For BaP, SDCESL achieved quantification limits of 0.019 ng mL-1 in river waters and 0.007 ng mL-1 in drinking waters. This work offers a sensitive, precise, accurate, rapid, simple and economic methodology for monitoring BaP in waters for public consumption, meeting all the requirements of the EC Directive 98/83/CE that fixes the maximum admissible limit for this polycyclic aromatic hydrocarbon in drinking waters at of 0.010 ng mL-1.     

Simple Fluorimetric Determination of Benzo[a]pyrene in Cigarette Smoke without Preseparation Procedure

Polycyclic aromatic hydrocarbons(PAHs)are important environmental pollutions originating from a wide variety of natural and anthropogenic sources.Benzo[a]pyrene is frequently sought as an indicator of the presence of other PAHs.Fluorescence spectrometry serves as a good technique to analyze PAHs with high sensitivity.However,this technique is unfavorable for the analysis of benzo[a]pyrene in multi-component PAHs because of spectral overlap.This complication can be simplified by using spec…     

固相萃取和气相-质谱法测定主流烟气中苯并[a]芘的研究

 提出了一种用于测定主流烟气中痕量苯并 [a]芘的方法。以甲醇 正庚烷萃取体系初步处理主流烟气中的总粒相物 (TPM) ,接着以KOH甲醇溶液数毫升洗涤正庚烷萃取液 ,再将正庚烷萃取液适当浓缩后经过酸化的硅胶固相萃取小柱 ,流出液用N2 吹干后以乙酸乙酯 2 0 0 μL定容 ,对苯并 [a]芘进行选择离子监测方式下的气相 质谱法定量测定。方法的分离效果及重现性好 ,可用于复杂体系中痕量组分苯并 [a]芘的定量测定。     

Room-temperature excitation-emission phosphorescence matrices and second-order multivariate calibration for the simultaneous determination of pyrene and benzo[a]pyrene

The present article describes the simultaneous phosphorimetric determination of pyrene and benzo[a]pyrene, two highly toxic polycyclic aromatic hydrocarbons, through excitation-emission phosphorescence matrices (EEPMs) and second-order calibration. The developed approach enabled us to determine both compounds at μg L⁻¹ concentration levels without the necessity of applying separation steps, as well as significantly reducing the experimental time. An artificial neural network (ANN) approach was applied to optimize the chemical variables which have an influence on the room-temperature phosphorescence emission of the studied analytes. The present study was employed for the discussion of the scopes of the applied second-order chemometric tools: parallel factor analysis (PARAFAC) and partial least-squares with residual bilinearization (PLS/RBL). The superior capability of PLS/RBL to model the profiles of other potentially interferent polycyclic aromatic hydrocarbons (PAHs) was demonstrated. The quality of the proposed method was established with the determination of both pyrene and benzo[a]pyrene in artificial and real water samples.     

Method validation for determination of the 15 European-priority polycyclic aromatic hydrocarbons in primary smoke condensates by gas chromatography/mass spectrometry: interlaboratory study

A collaborative study was conducted to validate an analytical method for quantification of the 15 polycyclic aromatic hydrocarbons (PAHs) regarded in 2002 as a health concern by the former Scientific Committee on Food of the European Commission (SCF) in primary smoke condensates. The method is based on gas chromatography/mass spectrometry of a cyclohexane extract with solid-phase cleanup through silica gel. The analytes were detected in the selected-ion monitoring mode and quantified by using 3 isotopically labeled internal standard compounds. Seventeen laboratories participated in the collaborative validation study, of which 12 reported valid results. The data were subjected to Cochran, single Grubbs, and double Grubbs tests for statistical outliers. A maximum of 2 outliers was eliminated before further statistical evaluation of the method performance characteristics. Depending on the analyte, the results showed relative standard deviations for repeatability between 4.2 and 30% and for reproducibility from 9.9 to 60%. The recoveries varied between about 50 and 85%, except those for cyclopenta[cd]pyrene, dibenzo[a,l]pyrene, and dibenzo[a,h]pyrene. Nevertheless, because Commission Directive 2005/10/EC allows for a recovery range of 50-120% for (BaP) benzo[a]pyrene in various foods, it can be concluded that the method performs appropriately within the analytical range between 5 and 25 microg/kg of primary smoke condensate. For BaP the validated analytical range covered 5-20 microg/kg, and for benzo[a]anthracene (BaA) 10-25 microg/kg. The method is suitable for monitoring BaP and BaA at their respective maximum permitted levels of 10 and 20 microg/kg. Three analytes, benzo[b]-, benzo[j]-, and benzo[k]-fluoranthene could not be separated by all of the participants and were therefore treated as the sum. Nevertheless, with this method the pattern of the respective concentrations of these 15 PAHs can be monitored in primary smoke condensate as suggested by the SCF.     

The determination of benzo[a]pyrene in the total particulate matter of cigarette smoke

A procedure for the isolation and determination of benzo[a]pyrene in the total particulate matter of cigarette smoke is described. Two high-pressure liquid chromatographic (HPLC) techniques are employed: a normal-phase, mu Bondapak-NH2, amino column is used for isolation of the benzo[a]pyrene fraction and a reversed-phase, Vydac 201TP54, polymeric octadecyl silane column is used for quantitation. Fluorescence detection is used in both modes of chromatography. The wavelengths of excitation and emission are evaluated for analytical detection. Extraction media and various isolation techniques are compared for their extraction efficiency and isolation from interferences, respectively. The procedure is efficient, reproducible, sensitive (3 pg), and gives results that compare favorably with other techniques reported in the literature for the B[a]P content of reference cigarettes, 1R1 and 1R4F.     

Structure and vibrational spectra of mononitrated benzo[a]pyrenes

The molecules benzo[a]pyrene (BaP) and 1-, 3-, and 6-nitrobenzo[a]pyrene (1-NBaP, 3-NBaP, 6-NBaP) are currently of significant interest due to their presence in respirable combustion exhaust particulates and their mutagenic and carcinogenic properties. Structure-function correlations as well as spectroscopic signatures for trace analysis are necessary for these benzo[a]pyrene derivatives. In this paper, detailed infrared and Raman spectroscopic data of BaP and its three mononitrated isomers are provided for the first time. By utilizing density functional theory (DFT, B3LYP method with 6-311+G basis set), the molecular geometries and the vibrational spectra are calculated. Good agreement is noted between the calculated and experimental geometry for BaP, and predictions of the vibrational data for all compounds are within approximately 5 cm-1 of the experimental data. Normal mode assignments are proposed with particular emphasis on the nitro group vibrations. The geometrical distortions of the BaP structure upon nitro group substitution and correlations between structural parameters and vibrational data as well as structure-function relationships related to the mutagenicity of this important class of polycyclic aromatic hydrocarbons are discussed.     

中心切割式多维气相色谱/质谱系统中中点限流器的改进及其在卷烟烟气中苯并[a]芘检测中的应用

对多维气相色谱的核心部件中点限流器进行了改进,用一段0.25mm i.d.毛细管柱取代石墨限流管,Y形玻璃压合连接器取代两孔石墨垫,显著提高了一维色谱保留时间的稳定性,保证了中心切割范围的准确性,且消除了石墨对苯并[a]芘的吸附残留。同时,将本系统应用于卷烟烟气中苯并[a]芘的检测。采用剑桥滤片捕集烟气粒相物,环己烷萃取,以氘代苯并[a]芘为内标,直接用中心切割式多维气相色谱/质谱(MDGC/MS)法测定。该法线性关系良好,其线性范围为1.47～29.4μg/L(r2=0.999 9);重复性好,测得实际样品中苯并[a]芘含量的相对标准偏差(RSD)为1.94%;回收率为90.74%～101.86%;检出限和定量限分别为0.31ng/支及1.03ng/支,可以满足检测要求。应用本系统对2R4F参比卷烟烟气中苯并[a]芘进行了检测,结果与文献报道值基本一致。     

Effects of cluster formation on spectra of benzo[a]pyrene and benzo[e]pyrene

Absorption and fluorescence emission spectra of the polycyclic aromatic hydrocarbons benzo[a]pyrene (BaP) and benzo[e]pyrene (BeP) in solution and adsorbed on silica have been obtained and compared to examine the spectroscopic effects of clustering. Molecular mechanics calculations with the UFF potential were done to optimize monomer, dimer and trimer geometries, and energy differences were determined by MP2/6-31G* calculations. Fluorescence emission spectra of adsorbed BeP and BaP display a red shift that progresses with increased loading, and the two differ in their photodegradation kinetics. The experimental and theoretical results are found to be consistent.     

Analytical study of cigarette smoke enriched in benzo[a]pyrene for use in model animal studies

Cigarette smoke has been significantly enriched in benzo[a]pyrene (BAP) by injecting 200 μl of a cyclohexane solution, containing a total of 40 μg of BAP, into a cigarette. After injection, the cigarette is conditioned and smoked according to standard protocol. When the cigarette smoke condensate is analyzed by fluorescence spectroscopy, liquid scintillation counting, gas chromatography with flame ionization detection, and gas chromatography-mass spectrometry, it is found that the level of BAP has increased by 1000 times with respect to levels reported for unenriched cigarette smoke. No chemical transformation of the BAP has been detected, and the BAP-enriched fraction does not appear to be perturbed to a detectable degree. Approximately 28% of the BAP is measured in the mainstream smoke, 46–48% in the sidestream smoke from the burning end of the cigarette, and 7% in the butt and ash. Correcting for analytical losses, about 10% appears to escape in the gaseous state. This material may prove suitable for model animal studies.     

Determination of benzo[a]pyrene in cigarette smoke condensate by liquid chromatography on amberlite xad-2

A method is described for the determination of benzo[a]pyrene in cigarette smoke condensate which utilizes chromatographic fractionation on Amberlite XAD-2. PAH are initially separated by step-wise gradient elution, progressing from reverse to normal-phase modes of operation. Other separation steps involve automated column chromatography on silica gel and thin-layer chromatography on 20% acetylated cellulose. Benzo[a]pyrene is finally determined by u.v. spectrophotometry and liquid scintillation counting of ¹⁴C—benzo[a]pyrene tracer. Results obtained compare favorably with those of the more traditional liquid—liquid extraction methods.     

Collection and analytical characterisation of the atmospheric particulate in the city of Bari

In this paper an application of new procedures for atmospheric particulate analysis is illustrated. PM10, PAHs (benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[j]fluoranthene (BjF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1, 2, 3-cd]pyrene (Ip), dibenzo[a, h]anthracene (DbA)) and heavy metals (Cu, Ni, Zn, Co, Mn, Cd, Fe and Pb) were investigated. PM10 determination was performed by gravimetric method, PAHs were measured by GC-MS, and heavy metals by HPIC. An air quality monitoring campaign on the territory of Bari municipality has been organised, and its results are shown.     

Error propagation as a factor in selection of measurement intervals for the determination of polycyclic aromatic hydrocarbons by second-derivative spectrofluorimetry

The most suitable wavelength intervals were selected for the determination of 4 polycyclic aromatic hydrocarbons (PAHs; benzo[g,h,i]perylene, dibenzo[a,h]anthracene, pyrene, and triphenylene) in very complex mixtures of 11 PAHs: anthracene, benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[g,h,i]perylene, benzo[k]fluoranthene, chrysene, dibenz[a,h]anthracene, phenanthrene, pyrene, and triphenylene. The multiple linear regression algorithm was applied to measurements made in several wavelength intervals previously selected on the basis of sensitivity and minimum number of interfering compounds. Of the different models obtained, those displaying minimum error propagation in the analytical result were selected. By applying the models proposed in this study, we precisely and accurately determined benzo[g,h,i]perylene, dibenz[a,h]anthracene, pyrene, and triphenylene in complex mixtures--a feat that could not be achieved by the use of constant-wavelength spectrofluorimetry in combination with second-derivative techniques.     

分子印迹聚合物选择性降低烟气中稠环芳烃类物质

以芘(PYR)为模板,由热引发本体聚合合成了芘分子印迹聚合物(MIP),考察了印迹聚合物的选择性吸附性能,采用Scatchard模型分析了印迹聚合物的结合特性,用离线固相萃取实验考察了印迹聚合物对同类底物的吸附能力,并将芘分子印迹聚合物应用到卷烟滤嘴中,用GC/MS法考察了卷烟主流烟气中稠环芳烃类物质释放量的变化。 结果表明,芘分子印迹聚合物具有选择性降低卷烟烟气中稠环芳烃类物质的功能,当MIP添加量为1.5 mg时,能将卷烟烟气中的苯并[a]芘(B[a]P)、苯并(a)蒽(B[a]A)和苣(CHR)的释放量分别降低31.08%、25.69%和27.33%。     

Determination of some polycyclic aromatic hydrocarbons in filter tar of Turkish cigarettes

A simultaneous determination method for the analysis of benzo[a]pyrene (BaP) and dibenzo[a,h]anthracene (DahA) in the filter tar of Turkish cigarettes has been developed. The method involved (a) the extraction of BaP and DahA with n-hexane from ACN solution in which the cigarette filters were extracted, and then (b) purification of the n-hexane extracts by elution on an XAD-2 column using n-hexane/dichloromethane (9:1, v/v) mixture. Separation and quantitative determination of BaP and DahA in the extracts were carried out by HPLC and fluorescence detection on a C18 RP column. The calculated recoveries for BaP and DahA were found in the range of 90-100% for each extraction and clean-up steps. Analysis of various filter tar of Turkish cigarettes showed that an average of 74.28 ng/filter of BaP and 5.24 ng/filter of DahA were present in Turkish cigarettes.     

Oxidized metabolites from benzo[a]pyrene, benzo[e]pyrene, and aza-benzo[a]pyrenes. A computational study of their carbocations formed by epoxide ring opening reactions

A DFT study aimed at understanding structure-reactivity relationships and fluorine substitution effects on carbocation stability in benzo[a]pyrene (BaP), benzo[e]pyrene (BeP), and aza-benzo[a]pyrene (aza-BaP) derivatives are reported. The relative energies of the resulting carbocations are examined and compared, taking into account the available biological activity data on these compounds. O-Protonation of the epoxides and diol epoxides leads to carbocation formation by barrierless processes. Charge delocalization modes in the resulting carbocations were deduced via NPA-derived changes in charges, and fluorine substitution effects were analyzed on the basis of charge density at different carbocation positions. Thus, fluorine substitution at sites bearing negative charge generated inductive destabilization of the carbocation, whereas a fluorine atom at a ring position which presented significant positive charge density produced a less pronounced destabilization due to fluorine p-pi back-bonding. Protonation reactions were also studied for the azaBaPs. In selected cases, the covalent adducts generated via bond formation with the exocyclic nitrogen of cytosine were computed and relative energies and geometries of the resulting adducts were examined.     

A simple method for the determination of benzo[a]pyrene and benzo[k]fluoranthene in a mixture

Atmospheric particulate matter is routinely analysed for the concentration of the carcinogen benzo[a]pyrene (BaP). Benzo[k]fluoranthene (BkF) has identical spectral characteristics and interferes in the fluorimetric estimation. A simple method for the determination of BaP in the presence of BkF is described. Based on quenching of the fluorescence of BaP by the addition of small amounts of nitromethane, the method can be used for accurate estimation for wide concentration ratios of BaP to BkF ranging from 0.1 to 10.0.     

腐殖酸磁固相萃取与高效液相色谱-荧光检测联用测定食用油中的苯并芘

采用简单的混合研磨方法制备磁性腐殖酸(MHAS)复合材料,并将其作为磁固相萃取的吸附剂选择性分离和富集食用油脂中的苯并芘(BaP)。结合高效液相色谱-荧光检测法(HPLC-FLD),建立了食用油中BaP检测的新方法。该方法整个样品前处理过程在15min内即可完成,对目标物BaP的检测限低至0.04ng/g,在0.1~100ng/g范围内线性良好(R=0.999),日内(n=5)和日间(n=3)相对标准偏差分别小于3.5%和15.8%。将该方法应用于多种食用油中BaP的检测,每种食用油中均有不同含量的BaP被检出,对12种常见食用油的加标回收率在74.2%至120.6%之间,相对标准偏差小于11.0%。     

Rapid SPE-HPLC determination of the 16 European priority polycyclic aromatic hydrocarbons in olive oils

Polycyclic aromatic hydrocarbons (PAHs) are a large class of organic compounds. It has been established that the main source of exposure to these compounds for human beings is through food, particularly fats and oils, due to the lipophilic nature of these polycyclic compounds. The aim of this work was to optimise and validate a method involving SPE and HPLC for rapid determination of the 16 European Union (EU) priority PAHs (required by the Recommendation 2005/108/EC) in vegetable oils. Two spectrofluorometric detectors and a UV-Visible detector in series were used to identify and quantify the target compounds. Linearity, recoveries, LOD, and LOQ were found to be in agreement with the performance criteria for benzo[a]pyrene (BaP) analysis as required by the Commission Directive 2005/10/EC, and satisfactory for all the compounds of interest, except for cyclopenta[c,d]pyrene, which presented a very low signal in the UV. Optimised chromatographic conditions for the separation of 25 PAHs, comprising both EPA and EU priority PAHs plus benzo[e]pyrene and benzo[b]chrysene, have been also proposed.