离子色谱法测定卷烟主流烟气中的氮氧化物

采用一种全新的离子色谱法测定卷烟主流烟气中氮氧化物,即采用装有5%三乙醇胺溶液的多孔玻板吸收瓶吸收卷烟主流烟气中NO2(NO先用CrO3氧化管氧化为NO2),使之转化为NO2-和NO3-,然后用离子色谱同时检测。由于采用合适的梯度淋洗条件,不需任何样品预处理即可直接检测,方法简便快速。结果表明,本法在0.5-10 mg/L具有良好的线性关系;相对标准偏差小于2%;NO2-和NO3-的检出限分别为0.04mg/L、0.05 mg/L;回收率为97%-101%。     

气相色谱-质谱联用法测定卷烟主流烟气中烟草特有亚硝胺

研究了用气相色谱-质谱联用法,用选择离子监测技术测定卷烟主流烟气中烟草特有亚硝胺N'-亚硝基去甲基烟碱(NNN)和4-(N-亚硝基甲氨基)-1-(3-吡啶基)-1-丁酮(NNK).在标准吸烟条件下,将烟气粒相物收集在剑桥滤片上,用柠檬酸-磷酸盐缓冲液和环己烷对粒相物共提取,提取液相继用碱性氧化铝层析柱和固相萃取法进一步纯化.选用选择离子监测技术对亚硝胺定性和定量.在进样量2μL时,方法检出限为9.83μg·L-1(NNN)和16.92 μg·L-1(NNK),线性范围0.1～5.0 mg·L-1,相关系数分别为0.998,0.996,回收率分别为91.0%,94.8%.     

超声提取-气相色谱-质谱法测定薄荷型卷烟烟丝及滤嘴中薄荷醇的含量

将2支剪碎的滤嘴(或1.000g卷烟烟丝)放入100mL锥形瓶中,加入40mL甲醇和80μL 50g·L~(-1)苯甲酸正丙酯内标溶液,80%超声功率条件下提取30min。取上清液,经0.45μm滤膜过滤后,以HP-INNOWAX色谱柱(30m×0.25mm,0.25μm)为固定相,采用气相色谱-质谱法测定其中薄荷醇的含量。质谱分析中采用电子轰击离子源,全扫描和选择离子监测模式。薄荷醇的质量浓度在10.0～400mg·L~(-1)内与对应的峰面积和内标峰面积的比值呈线性关系,检出限(3s)为0.17mg·L~(-1)。对卷烟烟丝和滤嘴样品分别进行组内、组间精密度试验,测定值的相对标准偏差(n=5)均小于5.0%。按标准加入法进行回收试验,回收率在94.0%～101%之间。     

全二维气相色谱/飞行时间质谱用于卷烟主流烟气中酚类化合物的表征

建立了卷烟主流烟气粒相物中酚类化合物组成研究的全二维气相色谱／飞行时间质谱方法,并用所建立的方法对一种市售混合型卷烟主流烟气粒相物中的酚类馏分组成进行了表征．采用TOFMS谱图库检索辅以二维“结构谱图”的定性手段,初步鉴定出了其中250个酚类化合物．这些酚类化合物包括66个烷基苯酚、47个烯基苯酚、57个萘酚、17个苯基苯酚、32个甲氧基苯酚、9个酚酮和15个酚醛化合物．同时对不同类型的酚类化合物在二维气相色谱上的分布模式进行了讨论．     

卷烟主流烟气中氨的捕集及其离子色谱法测定

设计了高效的烟气捕集装置,建立了一种稀硫酸吸收、离子色谱法测定的卷烟主流烟气中氨的分析新方法.与早期的比色法、容量法、氨电极法、气相色谱法相比,该方法快速、简便,不需要复杂的样品前处理,完成一次分析只需12 min.检出限为0.005 mg/L,RSD为3.7%,空白加标回收率在87%～102%之间,吸烟加标回收率在98%～106%之间.测定了国内50种主要品牌卷烟,其主流烟气中氨含量范围为6.50～14.22μg/支烟.     

卷烟主流烟气中挥发性醛酮和苯的P&T-GC分析

挥发性羰基化合物和苯是卷烟烟气中重要的有害物质,为此建立了P&T-GC法测定卷烟样品主流烟气中的乙醛、丙醛、丁醛、丙酮、2-丁酮和苯.该方法不用2,4-二硝基苯肼(DNPH)衍生化,不用有机溶剂萃取和浓缩,减少了对环境的污染,具有灵敏度高、检出限低、定量准确、操作简便等特点.结果表明:方法有较好的重复性,相对标准偏差在5.39%以下;检出限为0.85 ng/支～6.55 ng/支;6种物质的回收率在89.22%～98.21%之间.     

离子色谱法测定卷烟主流烟气中的气相氨北大核心CSCD

采用离子色谱法测定卷烟主流烟气中的气相氨。采用IonPac CS16阳离子分析柱和IonPac CG16阳离子保护柱,以0.045mol·L-1甲烷磺酸为淋洗液,电导检测器进行检测。气相氨的的质量浓度在0.01~1.0mg·L-1范围内呈线性,其检出限(3s)和测性下限(10s)分别为8.79×10-3μg·支-1和2.93×10-2μg·支-1。加标回收率在92.2%~103%之间,日内、日间相对标准偏差(n=5)均小于5.5%。采用此方法对七种卷烟主流烟气中气相氨的释放量进行了测定。     

主流卷烟烟气中气相自由基测定方法的改进

按照ISO 4387标准进行吸烟, 通过自行研制的捕集装置, 以2-苯叔丁基硝酮(PBN)的四氯化碳溶液捕集气相自由基. 将捕集到气相自由基的溶液先用液氮冷冻, 再定时解冻以抑制其衰减, 并有效地去除氧气对气相自由基定量分析的干扰, 获得理想的测定重复性. 用电子顺磁共振波谱仪(EPR)检测气相自由基, 以2,2,6,6-四甲基哌啶-1-氧(TEMPO)作为标准样品, 以碳酸钙稀释的煤粉作为校正样品, 定量计算气相自由基. 测定方法有较好的重复性和较高的灵敏度, 可以满足日常卷烟烟气气相自由基的定量分析的需要.     

固相萃取和气相色谱-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200 μL定容,对苯并[a]芘进行选择离子监测方式下的气相色谱-质谱法定量测定.方法的分离效果及色谱重现性好,可用于复杂体系中痕量组分苯并[a]芘的定量测定.     

Analysis of pyridines in mainstream cigarette smoke

A new technique has been developed for the quantitative analysis of pyridines in mainstream cigarette smoke using a GC-MS technique. For analysis, 10 cigarettes are smoked using conditions based on US Federal Trade Commission recommendations. The smoke is collected in a water trap and analyzed using a GC-MS technique. A standard or a fast GC separation can be applied for the analysis. The standard separation was followed by MS detection using selected ion monitoring (SIM) acquisition on a quadrupole instrument. The fast GC was followed by MS detection with total ion acquisition on a time-of-flight instrument. The levels of pyridine depend on the type of cigarette: for a full flavor cigarette pyridine is as high as 18.0 microg/cigarette (cig.). and for an ultra light cigarette is about 3.0 microg/cig. Substituted pyridines vary between 5.0 microg/cig. to 0.1 microg/cig. for a full flavor cigarette, and between 0.2 microg/cig. and a few ng/cig. for an ultra light cigarette. The reproducibility of the technique is very good, with less than 7-8% RSD in both separation procedures for most of the analyzed compounds.     

Identification and determination of mainstream and sidestream smoke components in different brands and types of cigarettes by means of solid-phase microextraction-gas chromatography-mass spectrometry

The qualitative and quantitative determination of components of mainstream and sidestream smoke has been performed by solid-phase microextraction-gas chromatography-mass spectrometry. Several brands and types of cigarettes sold in Italy were considered: normal, mild, light, extra light, some with filter and some without. Extraction of the analytes was performed by means of solid-phase microextraction (SPME) and the optimisation of the extraction procedure was performed by experimental design, taking into consideration type of fiber polymer, exposure temperature and time. Sixty-seven components of mainstream and sidestream smoke were identified. The quantified compounds (by means of deuterium-labelled isotopologues) were benzene, toluene, p-xylene, m-xylene, pyridine, o-xylene, limonene, naphthalene, phenol and nicotine. Finally, a comparison between the chemical profile of smoke from the different cigarettes was made.     

Study on the effect of potassium lactate additive on the combustion behavior and mainstream smoke of cigarettes

The influence of potassium lactate (PL) on the combustion behavior and semi-volatile compounds of tobacco during smoking is investigated in this study. The addition of PL showed no effect on the content of total particulate matter, nicotine-free dry particulate matter, puff number, and nicotine. Meanwhile, a 22.5 % increase in moisture content and 3 % decrease in CO content of mainstream smoke were observed when the added amount of PL was up to 2 %. The differential thermogravimetric curves indicated that PL decreased the maximum combustion rate and influenced the thermal degradation stage of tobacco by shifting the peak point of temperature to a higher value. The gas evolution profiles obtained from Fourier transform infrared spectroscopy during combustion showed that PL could lower the CO and CO₂ yield, but did not affect the generation of CH₄ and carbonyl compounds. A great variation in semi-volatile components of the mainstream smoke was also observed from the tobacco containing PL compared with the control. The comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry analysis showed that PL increased the yield of alcohols, lactons, miscellaneous oxygenated compounds and amides, but decreased that of aldehydes, acids, pyrroles and pyrazines. A small added amount (0.2 %) of PL reduced the content of total semi-volatile substances, ketones, esters, phenols, hydrocarbons, pyridines, tobacco alkaloids, and nitrogenous compound. However, the contents of these substances were not affected when the added amount was >0.2 %. PL bound the ash during combustion, thereby leading to the change of combustion behavior and certain smoke components.     

直接萃取-GC/MS法测定卷烟主流烟气中四种芳香胺

采用气相色谱/质谱法直接测定了卷烟主流烟气中的1-氨基萘、 2-氨基萘、 3-氨基联苯和4-氨基联苯等4种芳香胺.该方法直接用CH2Cl2溶剂超声振荡萃取滤片中的芳香胺,超声萃取的同时加入衍生试剂,使萃取和衍生化同步进行,萃取液过硅酸镁柱进行进一步纯化,然后旋转浓缩后进行GC/MS分析.方法的RSD在1.0%～3.7%之间,加标回收率在92.9%～101.1%之间.     

Artifactual chemiluminescence in the determination of nitrogen monoxide in the vapour phase of mainstream cigarette smoke

Evidence is presented for the artifactual chemiluminescence from olefins in the determination of nitrogen monoxide in the vapour phase of mainstream cigarette smoke. The interference may be quantified by measuring the residual chemiluminescence remaining in the vapour phase of mainstream cigarette smoke after 24 h. For the nitrogen monoxide analyser used, corrections to the yield of most cigarette brands retailed in the UK were found to be about 1.5 micrograms of nitrogen monoxide per puff, each machine puff being defined by international standards.     

Determination of rutin in cigarette tobacco, filters, mainstream smoke and burned ash of different branded cigarettes by high performance liquid chromatography

Tobacco consists of at least 3,800 chemical constituents. Among them, rutin is an important polyphenolic secondary metabolite in tobacco, which has positive actions such as antiallergic, anti-inflammatory and vasoactive, antitumor, antibacterial, antiviral and anti-protozoal properties. A high performance liquid chromatography method was used to analyze rutin in tobacco and filters, mainstream smoke, and burned ash of ten varieties of cigarettes made in China. The chromatographic analysis was performed on a Hypersil ODS2 column with a gradient elution of acetonitrile and water at a flow rate of 1.0 mL/min. Detection was carried out at 350 nm using a photodiode array detector. The calibration curves for the determination of analytes showed good linearity over the investigated ranges (R2 > 0.9998). Precision and reproducibility were evaluated by six replicated analyses, and the R.S.D. values were less than 0.59% and 1.53%. The recoveries were between 98.47 and 100.84%. Under the optimized conditions, namely 45 mL/g of solvent to solid ratio, 30 min of extraction time and 200 W of ultrasound power, the concentrations of rutin in tobacco and filter, mainstream smoke, burned ash of different brands cigarettes were 10.20-63.98, 0.10-0.32, 0.06-0.16 and 0 μg/per cigarette, respectively.     

Simultaneous determination of four tobacco-specific N-nitrosamines in mainstream smoke for Chinese Virginia cigarettes by liquid chromatography-tandem mass spectrometry and validation under ISO and “Canadian intense” machine smoking regimes

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining four tobacco-specific N-nitrosamines (TSNAs) in mainstream smoke from Chinese Virginia cigarettes was developed. Mainstream cigarette smoke particulate matter was collected on a Cambridge filter pad, further extracted using 100 mM ammonium acetate after 100 μL internal standard addition, and subsequently analyzed with LC-MS/MS. The limit of detection for NNN, NNK, NAT and NAB were 0.006, 0.013, 0.003 and 0.021 ng mL⁻¹ respectively, with a linear calibration range spanning 1-200 ng mL⁻¹. Intra- and inter-day precision for four TSNAs ranged from 3.3% to 8.5% and 2.3% to 10.1%; recovery was between 89.1% and 104.9% for Chinese Virginia cigarettes. The proposed method was applied to evaluate TSNAs yields for 39 commercially available cigarettes in Chinese market under ISO and “Canadian intense” machine smoking regimes, on the ground that it comes closest to representing smoke deliveries from human smoking. Total TSNAs emissions are more than double under the Canadian regime. TSNAs:nicotine ratios were used in our assay to show any differences in yield from different brands. TSNAs:nicotine levels show more than a 10-fold difference across brands and types (Chinese Virginia cigarettes and blended cigarettes) in the Chinese market.     

离子色谱法及聚类分析研究主流烟气中的有机酸

建立了超声辅助萃取-离子色谱法同时测定卷烟主流烟气中主要有机酸的方法.采用20 mL 30 mmol/L J NaOH溶液在50℃下对捕集了卷烟主流烟气的剑桥滤片超声萃取50 min,AS11-HC分离柱、Ion AG11-HC保护柱、ASRS-ULTRAⅡ抑制器,KOH溶液为淋洗液,用电导检测器同时测定了卷烟主流烟气中的乳酸、甲酸、乙酸、丙酸、苹果酸和草酸的含量.方法的线性范围1.0～400 mg/L,相关系数为0.9990～0.9995,相对标准偏差1.4%～4.8%,检出限0.03～0.09 mg/L,回收率为92%～104%.采用此方法测定了19种不同规格卷烟样品主流烟气中6种有机酸的含量,并且以6种有机酸为指标对样品进行了聚类分析.结果表明,6种有机酸的含量分布特征可反映不同等级卷烟产品的特性,可用于不用等级卷烟产品的比较和分类.     

Development of an improved method for the determination of polycyclic aromatic hydrocarbons in mainstream tobacco smoke

A gas chromatograph/mass-selective detection (GC/MS) method has been developed and validated for the quantitation of 16 polycyclic aromatic hydrocarbons found in mainstream tobacco smoke condensate. The utilization of two types of solid-phase extraction media combined with capillary column technology removed matrix interferences, afforded a significant reduction in analysis run time, and increased accuracy. Also, the addition of a chilled impinger was used to trap semi-volatile polycyclic aromatic hydrocarbons and to provide more accurate data. This was done without sacrificing the repeatability, reproducibility, and precision obtained in previously published methods. The development and validation studies discussed in this paper resulted in an improved, robust analytical method capable of increasing laboratory capacity and reducing sample reporting time.     

Direct determination of hydrogen cyanide in cigarette mainstream smoke by ion chromatography with pulsed amperometric detection

The determination of hydrogen cyanide in cigarette mainstream smoke has been achieved by ion chromatography (IC) with pulsed amperometric detection (PAD). The proposed method of totally trapping whole cigarette mainstream smoke by Cambridge filters, which are treated with sodium hydroxide/ethanol solution, possesses the advantage of fast analysis time over the widespread used solution absorption method. The possible co-existing interferents are evaluated under the optimized detection conditions and excellent recoveries of cyanide are obtained. The cyanide content of absorption solution can be directly determined by the optimized IC-PAD method without any pretreatments. The linear range is 0.0147-2.45 μg/mL with R2 value of 0.9997. The limit of the detection is 3 μg/L for a 25 μL injection loop. The overall relative standard deviation of the method is less than 5.20% and the recovery range from 94.3% to 101.0%. The results obtained from the developed method are in good agreement with that of continuous flow analyzer (CFA) method.