气相色谱-质谱联用内标法测定土壤中11种酞酸酯

建立了土壤中11种酞酸酯(PAEs)的气相色谱-质谱联用(GC-MS)内标分析方法,通过优化色谱柱升温程序和载气流量后,11种酞酸酯在18 min内得到良好的分离.同时以连续7次进样后计算PAEs峰面积响应值和峰面积变异系数为衡量指标,并逐个优化GC-MS的进样口温度、GC与MS的接口温度、进样方式和进样体积等GC-MS仪器操作参数,确定了GC-MS分析PAEs的最优条件为进样口温度250℃,接口温度280℃,载气流速1.2 mL.min-1,进样体积1.0μL,非脉冲进样方式.该分析条件下PAEs各组分的检出限(S/N=3)为0.37—1.97μg.L-1.该分析方法用于土壤样品中酞酸酯含量分析,并用苯甲酸苄酯(BenzylBenzoate)作为内标物,用内标法对11种肽酸酯进行定量,方法检出限0.01—0.07 mg.kg-1,土壤加标回收率基本在93.0%—115.0%范围内,结果可行.     

加速溶剂萃取/凝胶渗透色谱净化/气相色谱-负化学离子源质谱测定生物样品中的四溴联苯醚

建立了一种分析生物样品中四溴联苯醚（BDE-47）的方法.获得了优化的前处理条件和GC/MS检测条件,采用加速溶剂萃取（ASE）-凝胶渗透色谱（GPC）/多层硅胶-氧化铝复合柱净化,气相色谱-质谱（负化学离子源）（GC/NCI-MS）分析.以猪肝为基质的BDE-47加标回收率结果为77.3%—118.7%,相对标准偏差...     

气相色谱质谱-内标法检测染发剂中苯二胺

本文建立了利用萘做内标物定量检测染发剂中邻位、间位、对位苯二胺的气相色谱-质谱方法,方法线性关系良好,相关系数均大于0.997,平均加标回收率在81.01%-115.32%之间,相对标准偏差为4.98%-18.67%.该方法有效地提高了苯二胺的检测灵敏度,并可以准确鉴定染发剂中邻位、间位、对位苯二胺.     

海洋沉积物中甾醇类物质的气相色谱/质谱方法分析

应用超声提取技术,结合硅胶-中性氧化铝柱层析净化分离,BSTFA+1%TMCS衍生,及气相色谱-质谱定性定量技术,建立了海洋表层沉积物中8种甾醇类化合物的定量分析方法.实验采用正交实验优化了提取过程中提取剂种类、试剂体积和超声时间,同时对比并优化了柱层析淋洗液的配比、用量以及衍生剂的用量.结果表明,50 mL二氯甲烷/甲醇(V/V,2∶1),超声40 min,超声3次,总甾醇的萃取率可达99.6%;3 g硅胶+2 g中性氧化铝层析,35 mL二氯甲烷/甲醇(V/V,9∶1)淋洗净化回收最佳;8种甾醇在0—848μg.L-1范围内有良好的线性关系;方法检测限为1.2—2.4 ng.g-1.在3种浓度水平0.05、0.1和1.0μg.g-1下,其平均回收率为76.2%—100.9%,相对标准偏差为1.0%—10.3%.应用本方法检测大连湾的3个沉积物样品,8种甾醇的含量在0.079—6.833μg.g-1范围内.本方法的灵敏度高、准确度好,适合用于沉积物样品中甾醇物质的检测要求.     

高分辨气相色谱/高分辨质谱法测定南极样品中有机氯农药

建立了同位素稀释-高分辨气相色谱/高分辨质谱法(HRGC/HRMS)测定南极土壤、苔藓和地衣样品中23种有机氯农药的分析方法.样品经冷冻干燥、研磨处理后用正己烷∶二氯甲烷(1∶1,V∶V)混合溶剂进行加速溶剂萃取(ASE),萃取液经硅胶-氧化铝层析柱和C18小柱净化后,进HRGC/HRMS检测分析.样品中目标物定量采用平均相对响应因子法,6点标准曲线响应因子的相对标准偏差(RSD)≤20%,方法的线性范围为0.4—800μg·L-1,回收率在62%—101%之间.实际样品分析结果表明,23种OCPs的加标回收率为40%—100%,在土壤、苔藓和地衣样品中的检出限(LODs)分别为0.024—5.01、0.2—12.2、0.020—13.7 pg·g-1,可以满足南极环境样品中有机氯农药的检测分析.     

高分辨气相色谱/高分辨质谱联用分析氯苯类化合物中的二噁英类

多氯代二苯并-对-二噁英(Polychlorinated dibenzo-p-dioxins,PCDDs)和多氯代二苯并呋喃(Poly-chlorinated dibenzofurans,PCDFs)通称为二噁英(PCDD／Fs或dioxins),它们是氯代三环芳香化合物,由于氯原子的取代数目和位置不同,构成了75种PCDD和135种PCDF．在这210种化合物中,有17种(2,3,7,8位被氯原子取代)被认为对人类健康有巨大的危害,动物实验表明其具有强致癌性．其中,2,3,7,8-四氯代二苯并-对-二噁英(2,3,7,8-TCDD)在已知的化合物中毒性最大．二噁英类广泛分布于全球环境介质中,化学性质稳定,难以生物降解,可在食物链中富集．二噁英类往往作为副产品以杂质的形式存在于多种化工产品中,如氯酚、氯代苯氧酸型除草剂、多氯联苯、四氯苯醌等．     

气相色谱-质谱联用测定水产品中的合成麝香

利用快速溶剂萃取（ASE）和在线吸附净化,气相色谱-质谱（GC/MS）联用测定水产品中8种合成麝香.以正己烷为萃取溶剂,中性氧化铝为吸附剂,在100℃的温度下对水产品进行萃取.实验结果表明,方法的检测限为0.1—0.5 ng·g-1;在浓度1—80 ng·g-1的范围内,峰面积与样品浓度呈良好线性关系;8种合成麝香的回...     

甲草胺热裂解气相色谱-质谱分析

甲草胺是一种广泛用于农作物上的酰胺类除草剂.本文利用裂解气相色谱与质谱联用(Py-GC-MS)研究了甲草胺在热裂解温度200℃、400℃、600℃、800℃下的降解产物和热降解机理.实验结果表明,共有60种裂解产物被分离鉴定,随着温度的升高甲草胺显著分解,当裂解温度超过600℃时,大量的芳烃类、喹啉类、吲哚类化合物在高温裂解中产生,温度越高他们的相对含量也越高.基于对裂解产物的定性和它们含量的变化提出了甲草胺的热降解机理.     

吹扫-捕集/气相色谱/质谱分析水中挥发性有机化合物

吹扫 捕集与气相色谱 /质谱联用分析水中挥发性有机化合物是使用最为广泛的一种技术 .取 5ml水样 ,大多数目标化合物可在 0 5 μg·l- 1 或更低的浓度被定量 .如果取 2 5ml水样 ,就能得到更高的检测灵敏度 .安捷伦公司吹扫 捕集 /气相色谱 /质谱联用系统以其可靠的性能、高灵敏度和简单易用而在全球范围得到用户的认可 .同时安捷伦公司可提供专为分析环境中挥发性化合物而设计的软件、消耗品及气相色谱柱 ,能够保证任何一间实验室得到高质量、可靠的分析实验数据 .     

分子电性距离矢量预测多氯萘的正辛醇/空气分配系数

应用分子电性距离矢量(MEDV)对多氯萘(PCNs)的76种同系物进行结构表征,通过多元线性回归方法建立了PCNs的正辛醇/空气分配系数(lgKoA)与MEDV之间的定量结构一性质关系(QSPR),该模型具有显著的相关性(n=24,R=0.997,SD=0.088,F=417.546).采用逐步回归的方法(SMR)从原...     

臭氧应用于烟气净化的研究进展

烟气中所含的二氧化硫(SO2),氮氧化物(NOx),重金属汞(Hg)等污染物都能对人体健康及周围环境产生危害.本文综述了臭氧法应用于烟气净化的研究进展、工业应用及反应机理,探讨了臭氧同时脱硫脱硝脱汞的主要影响因素,介绍了臭氧发生技术的研究现状,并对臭氧应用于烟气净化进行了经济性分析,认为臭氧法脱除烟气中的多种污染物具有广泛的应用前景.     

利用EIA法快速筛查垃圾焚烧飞灰和烟气中的二恶英毒性水平

基于CAPE技术公司的兔子复合克隆抗体的二恶英(PCDD/F)酶免疫分析试剂盒,建立了快速检测垃圾焚烧飞灰和烟气中PCDD/F毒性(TEQ值)的方法.试剂盒的最低检测限为3.3pg·tube-1(即3.3pgTEQ每EIA试管),线性检测范围为10～30pg·tube-1.样品经甲苯索氏抽提后过硅胶柱连接小碳柱净化处理,TCDD/F的回收率大约为50%,与原飞灰PCDD/F分布模式相比净化处理后样品中的TCDD/F含量明显降低.用净化处理后的飞灰溶液作标准溶液,绘制PCDD/F剂量-效应关系曲线,定量分析了2个飞灰样品和2个烟气样品的TEQ浓度,结果表明分析样品的TEQ实测值(HRGC/HRMS分析获得)与预测值(标准曲线计算值)的相对偏差(Rd)均小于15%,说明用该方法定量分析垃圾焚烧飞灰和烟气中PCDD/F毒性是可行的.     

Determination of persistent organic pollutants by gas chromatography/laser multiphoton ionization/time-of-flight mass spectrometry

An authentic mixture of polychlorinated biphenyls was measured using a short wide-bore capillary column for the group separation of major components present in an actual sample of Kanechlor. The limits of detection were improved by ca. 2 fold in comparison with those obtained using a conventional capillary column, since the retention time was reduced and the amount of analytes introduced into the mass spectrometer per unit time could be increased. On the other hand, surface-water and sediment samples containing polycyclic aromatic hydrocarbons (PAHs) were collected from the river located in the vicinity of a waste water treatment plant. Even acenaphthylene, a minor component of the mixture could be measured for the sediment sample, and the concentrations were determined for several heavy PAHs. As demonstrated, a technique involving laser multiphoton ionization/time-of-flight mass spectrometry was useful as a sensitive and selective analytical tool for the trace analysis of persistent organic pollutants in an environmental sample.     

Sampling and analysis by GC/MS of the chitin synthesis inhibitors lufenuron and teflubenzuron in soil and soil invertebrates

A method for the measurement of benzoylphenyl ureas in soil, carabid beetles and earthworms was developed. These insecticides were transformed into their corresponding aniline derivatives in a hydrolytic step and subsequently measured by gas chromatography/mass spectrometry.     

Determination of pesticides in apples,grapes and apple juice from a Kosovo market by gradient liquid chromatography with tandem mass spectrometry

Apple, grape, and apple juice were analyzed for pesticides using a multireaction mode (MRM) method in samples taken from a Kosovo market. With this method it was possible to analyze about 100 pesticides in the ESI mode. In these samples some types of pesticides were found, but most of them did not exceed the maximum tolerance levels. In apple samples, six pesticides were detected but only three of them were in sufficient quantitites. Dimethoat was below the limit, while acephate and imazalil exceeded the limit. In grape and apple juice samples, all of pesticides which were found did not exceed the maximum tolerable limits.     

半挥发性有机污染物的气相色谱纯化方法

以六氯苯作为模型化合物,建立了半挥发性有机污染物样品净化的气相色谱方法.采用进样阀切换载气吹扫的进样方式,通过保留间隙柱和溶剂放空装置实现大体积进样,经过气相色谱分离后将分析物所在的半挥发性组分选择性冷凝在收集管中.本方法对模型化合物六氯苯的制备回收率为90%,对半挥发性有机污染物样品净化方法的发展具有重要意义.     

Identification of urinary metabolites in rats administered the fluorine-containing pyrethroids metofluthrin,profluthrin, and transfluthrin

The major metabolites in urine of rats administered the fluorine-containing pyrethroids transfluthrin, profluthrin, and metofluthrin, which are used widely recently as mosquito repellents or mothproof repellents, were identified to establish biological indexes for evaluating the absorption amounts of these pyrethroids in the general population. A single dose of 300?mg?kg^?1 body weight of each pyrethroid was separately administered intraperitoneally to male Sprague-Dawley rats and urine samples were collected until 24 hours after the administration. The metabolites identified by gas chromatography-mass spectrometry were as follows: 2,3,5,6-tetrafluorobenzyl alcohol, 2,3,5,6-tetrafluorobenzoic acid, and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (DCCA) for transfluthrin; 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol, 4-methyl-2,3,5,6-tetrafluorobenzoic acid, 4-hydroxymethyl-2,3,5,6-tetrafluorobenzyl alcohol (HOCH₂–FB–Al), and 2,2-dimethyl-3-(1-propenyl)-cyclopropanecarboxylic acid (MCA) for profluthrin; 4-methoxymethyl-2,3,5,6-tetrafluorobenzyl alcohol, HOCH₂–FB–Al and MCA for metofluthrin. In addition, several compounds estimated to be metabolites were detected as follows: hydroxylated DCCA and its lactone for transfluthrin; 4-hydroxymethyl-2,3,5,6-tetrafluorobenzoic acid (HOCH₂–FB–Ac), hydroxylated MCA and its lactone for profluthrin; 4-methoxymethyl-2,3,5,6-tetrafluorobenzoic acid, HOCH₂–FB–Ac, hydroxylated MCA, and its lactone for metofluthrin. The pyrethroids administered underwent metabolic reactions such as ester hydrolysis and oxidation, and most of the metabolites were excreted as their conjugates into urine. These findings should be useful as basic data for evaluating the health effects of exposure to pyrethroids for the general population.