室内空气中挥发性有机化合物污染及检测方法

室内空气中挥发性有机污染物的释放严重影响了室内空气质量,本文较详细的叙述了这些有机污染物的来源、种类及处理方法等,并对空气中VOCs的采集和检测方法作以介绍,阐述了不同机制的热解吸仪与气相色谱联用时的优缺点及其应用．     

水性涂料中挥发性有机化合物的气相色谱-质谱法测定

建立了内墙涂料中24种挥发性有机化合物(VOCs)的GC-MS检测方法,重点研究了现有检测方法分离度差和回收率低的问题,采用无水硫酸钠净化、二氯甲烷超声和膜过滤提取体系,改善了各种化合物的回收率,特别是提高了二元醇类化合物的回收率,优化后的实验条件下,样品的加标回收率为70%~94%,相对标准偏差不大于6.8%,检出限为3.1~10.6 mg/L。在30~300 mg/L范围内,方法的线性关系良好,相关系数大于0.99。该方法简便、快速、灵敏、精密度好,完全满足进出口水性涂料中常见的24种挥发性有机化合物的检测要求。     

Development of a Water Matrix Certified Reference Material for Volatile Organic Compounds Analysis in Water

Water matrix certified reference material (MCRM) of volatile organic compounds (VOCs) is used to provide quality assurance and quality control (QA/QC) during the analysis of VOCs in water. In this research, a water MCRM of 28 VOCs was developed using a “reconstitution” approach by adding VOCs spiking, methanol solution into pure water immediately prior to analysis. The VOCs spiking solution was prepared gravimetrically by dividing 28 VOCs into seven groups, then based on ISO Guide 35, using gas chromatography-mass spectrometry (GC-MS) to investigate the homogeneity and long-term stability. The studies of homogeneity and long-term stability indicated that the batch of VOCs spiking solution was homogeneous and stable at room temperature for at least 15 months. Moreover, the water MCRM of 28 VOCs was certified by a network of nine competent laboratories, and the certified values and expanded uncertainties of 28 VOCs ranged from 6.2 to 17 μg/L and 0.5 to 5.3 μg/L, respectively.     

吹扫捕集–气相色谱–质谱法同时测定环境水中101种挥发性有机物

建立吹扫捕集–气相色谱–质谱联用法测定环境水中101种常见挥发性有机物(VOCs)的方法。通过加热吹扫,样品水中的VOCs富集于捕集管中,以DB–624(60 m×0.25 mm,1.4μm)色谱柱分离,内标法定量。结果表明,101种挥发性有机物(VOCs)色谱分离效果良好,质量浓度在0.5~50 ng/mL范围内与色谱峰面积均呈线性关系,高沸点VOCs线性范围较窄。方法定量限(10 S/N)为0.11~0.77 ng/mL,均低于GB 3838–2002《地表水环境质量标准》、GB 5749–2006《生活饮用水卫生标准》及国外相关标准的限值。平均加标回收率在70.3%~123.6%之间,测定结果的相对标准偏差不大于8.8%(n=6)。该方法快速、简便,适用于环境水中挥发性有机化合物的分析检测。     

饮用水中挥发性有机物(VOCs)的GC-MS分析

用顶空－毛细管气相色谱－质谱联用仪测定了北京主要区域的自来水,北京目前市场销售的瓶装饮用水（包括天然矿泉水,纯净水等）中２３种挥发性有机物（ＶＯＣｓ）（包括有机氯化物,有机溴代物及苯系物等）的浓度,并与其它城市（如天津,上海,兰州等地）的自来水中ＶＯＣｓ的浓度进行了比较,结果表明北京市区内自来水及大多数市售瓶瓶饮用水中ＶＯＣｓ含量很低。     

吸附—光催化联用去除室内挥发性有机物*

多孔吸附剂吸附和纳米TiO₂光催化是目前室内挥发性有机物（VOCs）去除所采用的主要手段。但存在吸附剂容量有限、饱和失效、TiO₂光催化剂活性低、失活和负载困难等问题。多孔吸附剂与纳米TiO₂联用,通过TiO₂光催化作用可实现吸附剂的原位再生,增加吸附剂的吸附容量;通过多孔吸附剂的吸附作用可为TiO₂光催化提供高浓度污染环境,提高催化剂活性,抑制催化剂失活,消除水蒸气分子对TiO₂表面活性吸附位的竞争吸附,解决催化剂分离难题;从而实现对室内VOCs污染的高效深度净化。本文对近年来多孔吸附剂与纳米TiO₂光催化联用去除室内VOCs进行了综合评述。介绍了吸附—光催化联用去除室内VOCs的多孔吸附剂类型,吸附/光催化复合材料的制备方法及常用反应器,分析了吸附—光催化联用去除室内VOCs过程中水蒸气、催化剂失活对光催化的影响等问题。     

静态顶空/气相色谱-质谱法同时测定化妆品中22种有毒挥发性有机溶剂残留

以2015版《化妆品安全技术规范》中规定的常见禁用及限用有毒挥发性有机溶剂为研究对象,建立了静态顶空/气相色谱-质谱法(SHS/GC-MS)同时测定化妆品中22种有毒挥发性有机溶剂(VOC)(二氯甲烷、顺式-1,2-二氯乙烯、反式-1,2-二氯乙烯、2-氯-1,3-丁二烯、三氯甲烷、1,2-二氯乙烷、苯、四氯化碳、三氯乙烯、甲苯、四氯乙烯、氯苯、乙苯、三溴甲烷、间二甲苯、对二甲苯、苯乙烯、邻二甲苯、异丙苯、1,4-二氯苯、1,2-二氯苯、六氯丁二烯)残留的检测方法。试样在80℃下30 min静态顶空,经DB-1柱分离后,采用选择离子监测模式(SIM)进行定性定量分析。优化了顶空、色谱和质谱参数,结果表明:22种VOC在0.5~50 ng/m L浓度范围内均呈良好的线性关系,相关系数均大于0.99,在1.0,2.0,5.0 ng/m L 3个浓度加标水平下的平均回收率为80.3%~102.7%,相对标准偏差(RSD,n=6)为6.4%~9.9%,检出限为0.2~5.0 ng/g。结果表明,该方法简便、灵敏、准确,具有良好的重现性和稳定性,适合于化妆品中22种VOC残留的筛查和确证检测。     

A Study on VOCs Released by Lung Cancer Cell Line Using GCMS-SPME

The gas chromatography mass spectrometry (GCMS) with combination of Solid Phase Micro-extraction (SPME) was used to study the volatile organic compounds (VOCs) which emitted by the in-vitro cultured human cells and compared with documented volatile biomarker of lung cancer. For this purpose, the lung cancer cell (A549) and non-cancerous lung cell (WI38VA13) were cultured in identical growth medium, concurrently. The VOCs in the headspace of the cell cultures and the blank growth media (reference sample) were collected directly from the culture flask using SPME for 15minutes. The results show that two different volatile metabolites were screened out between A549 cells and Wi38VA13 cells. A549 cell found to emit 2 noticeable VOC which are decane and heneicosane. While for WI38VA13, the VOCs released were 1-Heptanol and heptadecane. The acquired VOCs were compared with the previous studies. The findings in this work conclude that the specific VOC of cells can be act as their odour signature and can be used to provide non-invasively screening of lung cancer using gas array sensor devices.     

气相色谱法检测空气中有机物挥发总量的不确定度评定

对气相色谱法测定室内有机物挥发总量(TVOC)过程中可能引入的不确定度进行了分析和评定。通过实验数据计算得出室内空气中TVOC浓度的不确定度为:当取置信概率为95%,包含因子k=2,则其扩展不确定度Urel=13.73%。通过对不确定度的分析,指出在检测过程中质量控制的关键在于标准物质的浓度和气相色谱分析样品过程,该两项引入的不确定分量占总相对标准不确定度的93%,并提出了质量控制改进方法。     

液态乳制品包装材料中VOCs迁移安全性研究

利用顶空/气相色谱-质谱(HS/GC-MS)联用法对百利包、利乐包、塑杯3种乳制品包装材料中的挥发性有机物(VOCs)进行迁移安全性研究。结果表明,平衡温度与保温时间对包装中的VOCs有不同程度的影响。百利包中均含有苯,部分含有异丙醇、乙苯、间/对二甲苯、邻二甲苯,包装材料中VOCs含量为85.64~102.10 ng/cm2;利乐包含有苯、间/对二甲苯、邻二甲苯,部分含有异丙醇、乙酸乙酯、乙酸丁酯、乙苯,包装材料中VOCs含量为54.77~75.16 ng/cm2;塑杯均含有苯,部分含有异丙醇、间/对二甲苯、邻二甲苯,包装材料中VOCs含量为82.63~171.25 ng/cm2。利用迁移模型对乳制品进行研究,得出苯迁移最坏情况为0.885×10-3mg/kg;穿过0.015 cm厚度包装材料所需的时间为76 d,大于其保质期45 d。     

Response surface optimisation applied to a headspace-solid phase microextraction-gas chromatography-mass spectrometry method for the analysis of volatile organic compounds in water matrices

A new method for the simultaneous determination of 12 volatile organic compounds (trans-1,2-dichloroethene, 1,1,1-trichloroethane, benzene, 1,2-dichloroethane, trichloroethene, toluene, 1,1,2-trichloroethane, tetrachloroethene, ethylbenzene, m-, p-, o-xylene) in water samples by headspace solid phase microextraction (HS–SPME)–gas chromatography mass spectrometry (GC–MS) was described, using a 100?µm PDMS (polydimethylsiloxane) coated fibre. The response surface methodology was used to optimise the effect of the extraction time and temperature, as well as the influence of the salt addition in the extraction process. Optimal conditions were extraction time and temperature of 30?min and ?20°C, respectively, and NaCl concentration of 4?mol?L^?1. The detection limits were in the range of 1.1?×?10^?3–2.3?µg?L^?1 for the 12 volatile organic compounds (VOCs). Global uncertainties were in the range of 4–68%, when concentrations decrease from 250?µg?L^?1 down to the limits of quantification. The method proved adequate to detect VOCs in six river samples.     

Determination of volatile organic compounds in human breath for Helicobacter pylori detection by SPME-GC/MS

Helicobacter pylori living in the human stomach release volatile organic compounds (VOCs) that can be detected in expired air. The aim of the study was the application of breath analysis for bacteria detection. It was accomplished by determination of VOCs characteristic for patients with H. pylori and the analysis of gases released by bacteria in suspension. Solid-phase microextraction was applied as a selective technique for preconcentration and isolation of analytes. Gas chromatography coupled with mass spectrometry was used for the separation and identification of volatile analytes in breath samples and bacterial headspace. For data calculation and processing, discriminant and factor analyses were used. Endogenous substances such as isobutane, 2-butanone and ethyl acetate were detected in the breath of persons with H. pylori in the stomach and in the gaseous mixture released by the bacteria strain but they were not identified in the breath of healthy volunteers. The canonical analysis of discrimination functions showed a strong difference between the three examined groups. Knowledge of substances emitted by H. pylori with the application of an optimized breath analysis method might become a very useful tool for noninvasive detection of this bacterium.     

热脱附-气相色谱-质谱法应用于工业源废气中挥发性有机物的目标和非目标筛查

建立了固相吸附热脱附-气相色谱-质谱(TD-GC-MS)综合筛查工业源废气中挥发性有机物(VOCs)的方法。对两种型号的固相吸附管进行了比较,最终选择使用Tenax SS TD Tubes吸附管。气体样品以恒定流速通过吸附管,富集分析物,经热脱附后,用GC-MS进行检测,目标化合物以内标法定量,非目标化合物的含量以甲苯的响应系数计算。方法检出限为1.06~5.44 ng,以采样体积300 mL计算,目标化合物的检出限为0.004~0.018 mg/m~3。吸附管平均加标回收率为78.4%~89.4%,相对标准偏差为3.9%~14.4%(n=7)。应用该方法对大连市某垃圾焚烧发电厂排放的废气进行VOCs目标及非目标化合物综合筛查,共检出29种VOCs,其中仅5种VOCs为预先设定的目标化合物,另外24种为非目标化合物,5种目标化合物含量仅占所有检出物总量的26.7%。证明了工业源废气VOCs分析中非目标化合物筛查的重要性,该研究思路对完整测定工业源挥发性有机污染物分布具有一定的借鉴意义。     

离子液体中的聚合反应研究进展

室温离子液体是一种新兴的可替代挥发性有机化合物（VOCs）的绿色溶剂和高效的反应介质，为减少或消除化学反应和过程工程中的环境问题提供了重要的途径。以离子液体为反应介质进行聚合反应，可消除或减小VOCs的危害，也可实现催化剂的有效回收利用和聚合物的纯化，更好地控制聚合反应及聚合产物的结构与性质、乃至直接用作高效的聚合催化剂。本文综述近年来离子液体中聚合反应的研究现状及最新进展，分析现存的问题，并展望今后的发展方向。     

Chemical Composition and In Vitro Antioxidant Activity of Sida rhombifolia L. Volatile Organic Compounds

In the current study, the phytochemical constituents of volatile organic compounds (VOCs) obtained from Sida rhombifolia L. were identified by GC-FID and GC-MS analysis. A total of 73 volatile organic compounds were identified. The major components of S. rhombifolia VOCs were identified as palmitic acid (21.56%), phytol (7.02%), 6,10,14-trimethyl-2-pentadecanone (6.30%), oleic acid (5.48%), 2-pentyl-furan (5.23%), and linoleic acid (3.21%). The VOCs are rich in fatty acids (32.50%), olefine aldehyde (9.59%), ketone (9.41%), enol (9.02%), aldehyde (8.63%), and ketene (6.41%). The antioxidant capacity of S. rhombifolia VOCs was determined by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), 2,2-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) diammonium salt (ABTS), and ferric reducing/antioxidant power (FRAP) methods with butylated hydroxytoluene (BHT) and Trolox as standard. The VOCs showed dose-dependent antioxidant activity with IC50 (50% inhibitory concentration) values of 5.48 ± 0.024 and 1.47 ± 0.012 mg/mL for DPPH and ABTS assays, respectively. FRAP antioxidant capacity was 83.10 ± 1.66 mM/g. The results show that the VOCs distilled from S. rhombifolia have a moderate antioxidant property that can be utilized as a natural botanical supplement or an antioxidant.     

Application Potential of Bacterial Volatile Organic Compounds in the Control of Root-Knot Nematodes

Plant-parasitic nematodes (PPNs) constitute the most damaging group of plant pathogens. Plant infections by root-knot nematodes (RKNs) alone could cause approximately 5% of global crop loss. Conventionally, chemical-based methods are used to control PPNs at the expense of the environment and human health. Accordingly, the development of eco-friendly and safer methods has been urged to supplement or replace chemical-based methods for the control of RKNs. Using microorganisms or their metabolites as biological control agents (BCAs) is a promising approach to controlling RKNs. Among the metabolites, volatile organic compounds (VOCs) have gained increasing attention because of their potential in the control of not only RKNs but also other plant pathogens, such as insects, fungi, and bacteria. This review discusses the biology of RKNs as well as the status of various control strategies. The discovery of VOCs emitted by bacteria from various environmental sources and their application potential as BCAs in controlling RKNs are specifically addressed.     

热脱附-气相色谱-质谱法测定环境空气中67种挥发性有机物

采用热脱附-气相色谱-质谱法,建立了同时分析环境空气中67种挥发性有机物的分析方法。对比了5种不同填充材料不锈钢吸附管对78种挥发性有机物的吸附能力。填充材料为Tenax TA和Carbograph 1TD的混合填料吸附管对分析物的捕集效果最好,在30 mL/min高纯He气持续吹脱45 min的情况下,未发生穿透（即穿透率小于10%）的化合物达67种,分析物的种类包括芳香烃、脂肪烃、卤代烃和含氧挥发性有机物等。优化了使用该吸附管测定67种目标物时的热脱附条件。在5~100 ng范围内,目标化合物的色谱响应值与其量间具有良好的线性关系,其相关系数（r）均在1.0000~0.9977之间。方法检出限为0.3~2.4 ng,以采样体积1 L计算,检出限为0.3~2.4 μg/m³。加标量为20 ng时,7次重复实验目标化合物回收率均在81.6%~114.9%之间,目标化合物的相对标准偏差为1.2%~10.1%。采用该方法对某车厢内空气进行了检测,检出了包括酯类、卤代烷烃、卤代烯烃以及芳香族化合物在内的19种目标化合物,其范围为1.1~84.1 μg/m³。该方法准确、可靠、灵敏度高,实现了对环境空气中67种目标污染物的准确定量。     

Elicitor-Induced VOC Emission by Grapevine Leaves: Characterisation in the Vineyard

The present study is aimed at determining whether leaf volatile organic compounds (VOCs) are good markers of the grapevine response to defence elicitors in the field. It was carried out in two distinct French vineyards (Burgundy and Bordeaux) over 3 years. The commercial elicitor Bastid^® (Syngenta, Saint-Sauveur, France) (COS-OGA) was first used to optimise the VOCs’ capture in the field; by bagging stems together with a stir bar sorptive extraction (SBSE) sensor. Three elicitors (Bastid^®, copper sulphate and methyl jasmonate) were assessed at three phenological stages of the grapevines by monitoring stilbene phytoalexins and VOCs. Stilbene production was low and variable between treatments and phenological stages. VOCs—particularly terpenes—were induced by all elicitors. However, the response profiles depended on the type of elicitor, the phenological stage and the vineyard, and no sole common VOC was found. The levels of VOC emissions discriminated between weak (Bastid^® and copper sulphate) and strong (methyl jasmonate) inducers. Ocimene isomers were constitutively present in the overall blends of the vineyards and increased by the elicitors’ treatments, whilst other VOCs were newly released throughout the growing seasons. Nonetheless, the plant development and climate factors undoubtedly influenced the release and profiles of the leaf VOCs.     

Mesoporous silicate MCM-48 as an enrichment medium for ambient volatile organic compound analysis

This study investigated the sorption/desorption properties of MCM-48 and its applicability as a sorbent for on-line gas chromatographic analysis of ambient volatile organic compounds (VOCs). To establish a valid comparison, commercially available carbon sorbents were evaluated under similar analytical conditions. Two trapping temperatures of 30 °C and −20 °C, representing ambient and sub-ambient temperatures, were tested by trapping a full range of VOCs from C₂–C₁₂. At ambient temperatures, due to the mesoporosity, the MCM-48 showed considerably limited trapping efficiency compared to microporous carbon sorbents on the highly volatile section of VOCs and only began to show effective trapping for compounds larger than C₇. Cooling to sub-ambient temperatures (e.g., −20 °C) extended the effective trapping down to C₄ VOCs, drastically increasing the applicability of MCM-48 as an in-line enrichment medium for gas chromatographic analysis of VOCs. The mesoporosity of MCM-48 also aided desorption. Much lower desorption temperatures (100–180 °C) were required for full desorption as compared to the temperatures (greater than 200 °C) required for carbon sorbents. Moreover, the easy desorption was accompanied by a low memory effect, as the large pores of MCM-48 can clean up more efficiently after desorption, with little residue left behind.     

Biogenic volatile organic compounds (BVOC) in ambient air over Hong Kong: analytical methodology and field measurement

In this paper, an analytical method using a simple semi-manual cryo-trap technique coupled to gas chromatograph with flame ionisation detector (GC-FID) was developed for the determination of biogenic volatile organic compounds (BVOC) in ambient air. Five common BVOC species have been tested, including isoprene and 4 monoterpenes, i.e. α-pinene, β-pinene, 3-carene (Δ) and limonene. The detection limits were estimated to be about 20 ppt for isoprene and 10 ppt for monoterpenes, with sample injection volume of 50 mL. Based on vegetation types, field measurement work was conducted over urban and rural sites of Hong Kong during summer and winter of 2007. Canister sampling technique was applied in the field measurement. Isoprene contents in rural ambient air were found to be in the range of 60～1560 ppt in winter and 260～3270 ppt in summer, respectively. However, in the measurement of monoterpenes, due to their extremely low concentration in the air samples, only β-pinene and limonene were detected by the developed analytical method.