交替三线性分解算法与HPLC-DAD相结合用于硝基苯类化合物的二阶校正

硝基苯类化合物是重要的有机化工原料,可用作染料、制药、橡胶和炸药等的生产原料或中间体．工厂在生产过程中所排放的含有硝基苯类的废水会污染环境水体,因此对硝基苯类含量进行测定具有重要的意义．目前,测定方法主要采用高效液相色谱法和气相色谱法．     

环境样品中硝基苯类化合物的分析方法研究进展

主要介绍了我国近年来在环境样品中硝基苯类化合物的分析研究进展,内容包括:光度法(还原-偶氮光度法、阻抑动力学光度法、化学计量学分光光度法、人工神经网络-分光光度法)、气相色谱法(固相微萃取-毛细管气相色谱法、树脂吸附-气相色谱法、液-液微萃取气相色谱法、超声萃取-气相色谱法)、高效液相色谱法(反相高效液相色谱法、固相萃取-高效液相色谱法)和极谱法等分析方法。     

一种塑料制品中氯苯类化合物的测定方法

本发明涉及氯苯类化合物的检测技术,尤其涉及一种塑料制品中氯苯类化合物的测定方法,包括如下步骤:(1)选取样品,使用高分子材料碎样机粉碎成均匀性样品;(2)取样加入溶剂,密塞,于微波萃取仪中萃取,萃取液过滤,用氮气中吹,待净化;(3)使用溶剂活化PA小柱,将样品加入溶剂溶解,用溶剂淋洗,用氮气吹干,用丙醇定容,(4)分别吸取待测的标准溶液和样品溶液,注入气相色谱–质谱仪,分别进行测定,最后计算样品中氯苯类化合物的含量。本发明的测定方法可以同时检测出塑料中12种氯苯类有机化合物,检出限低,精确度高,检测周期短,抗干扰能力强,方法快速稳定。     

毛细管柱气相色谱法测定水中氯苯类化合物

提出了应用毛细管气相色谱法测定水样中11种氯苯类化合物。水样以石油醚提取,用AC-20毛细管柱分离,经电子捕获检测器检测。11种氯苯类化合物的质量浓度均在一定的范围内与其峰高呈线性关系,方法的检出限(3S/N)在0.005～0.038μg.L-1之间。方法用于饮用水和水源水中氯苯类化合物的测定,加标回收率在85.2%～101.0%之间,测定值的相对标准偏差(n=8)在3.4%～5.2%之间。     

腌制食品中N-亚硝胺类化合物分析方法的研究进展北大核心CSCD

本文简要介绍了腌制食品中N-亚硝胺类化合物的种类及特性,重点综述了气相色谱法、气相色谱-质谱法、液相色谱法、液相色谱-质谱法和胶束电动毛细管色谱法等技术在腌制食品中N-亚硝胺类化合物分析中的应用进展(引用文献39篇)。     

甲苯类化合物的选择性氧化

综述了以O2为清洁氧源甲苯类化合物的气相和液相选择性氧化。甲苯类化合物的气相选择性氧化中主要介绍了金属氧化物、分子筛和负载型催化剂并对影响催化剂活性和选择性的因素进行了分析;甲苯类化合物的液相选择性氧化中重点介绍了MC(mid-century)催化体系及其反应机理方面的研究进展,并特别介绍了仿生催化在甲苯类化合物催化氧化中的应用。对各催化氧化体系的应用前景进行了展望。     

腌制食品中N-亚硝胺类化合物分析方法的研究进展

本文简要介绍了腌制食品中N-亚硝胺类化合物的种类及特性,重点综述了气相色谱法、气相色谱-质谱法、液相色谱法、液相色谱-质谱法和胶束电动毛细管色谱法等技术在腌制食品中N-亚硝胺类化合物分析中的应用进展(引用文献39篇)。     

甲苯类化合物的选择性氧化

综述了以O2为清洁氧源甲苯类化合物的气相和液相选择性氧化.甲苯类化合物的气相选择性氧化中主要介绍了金属氧化物、分子筛和负载型催化剂并对影响催化剂活性和选择性的因素进行了分析;甲苯类化合物的液相选择性氧化中重点介绍了MC (mid-century)催化体系及其反应机理方面的研究进展,并特别介绍了仿生催化在甲苯类化合物催化氧化中的应用.对各催化氧化体系的应用前景进行了展望.     

甲苯类化合物的选择性氧化

综述了以O2为清洁氧源甲苯类化合物的气相和液相选择性氧化.甲苯类化合物的气相选择性氧化中主要介绍了金属氧化物、分子筛和负载型催化剂并对影响催化剂活性和选择性的因素进行了分析;甲苯类化合物的液相选择性氧化中重点介绍了MC (mid-century)催化体系及其反应机理方面的研究进展,并特别介绍了仿生催化在甲苯类化合物催化氧化中的应用.对各催化氧化体系的应用前景进行了展望.     

蛋白质对测定水产品中氯苯类化合物的影响及消除

提出了气相色谱-质谱法测定水产品中1,3-二氯苯,1,2-二氯苯,1,2,4-三氯苯等3种氯苯类化合物含量的方法。采用荧光猝灭法研究了氯苯类化合物与蛋白质之间的结合作用,结果表明氯苯类化合物与鱼血清白蛋白之间存在较强的结合作用。水产品样品以丙酮-磷酸氢二钾-水双水相体系进行前处理。在气相色谱分离中用DB-WAX毛细管色谱柱为固定相,在质谱分析中采用选择离子监测模式。3种氯苯类化合物的质量浓度均在0.5~5.0mg·L-1范围内与其峰面积呈线性关系。以空白样品为基体进行加标回收试验,所得回收率在77.0%~116%之间,相对标准偏差(n=6)在2.6%~7.1%之间。     

Chromatography as a reference technique for the determination of clinically important steroids

Chromatographic methods (paper chromatography, thin layer chromatography, high performance liquid chromatography, gas chromatography and gas chromatography-mass spectrometry) for the determination of clinically important steroids in biological specimens are reviewed. The emphasis is on the use of gas chromatography, gas chromatography-mass spectrometry and high performance liquid chromatography as reference rather than routine techniques. Chromatographic methods are compared with colorimetric, fluorimetric and radioimmunoassay procedures in terms of simplicity of operation, cost and ability to analyse large numbers of specimens. The importance of correct specimen collection and storage are discussed. Sample preparation techniques for the various analytical methods are described. These include extraction of free and conjugated steroids from serum, plasma, urine and saliva by solvent partition, with polymer-based resins such as Amberlite XAD-2, DEAE-Sephadex and Sephadex resins bonded with various other function groups and, more recently, with chemically bonded reversed-phase silicas.     

Capillary electrophoresis-based methods for the determination of lipids--a review

Capillary electrophoresis (CE) is a high-resolution technique for the separation of complex biological and chemical mixtures. CE continues to emerge as a powerful tool in the determination of lipids. Here we review the analytical potential of CE for the determination of a wide range of lipids. The different classes of lipids are introduced, and the different modes of CE and optimization methods for the separation of lipids are described. The advantages and disadvantages of the different modes of CE compared to traditional methods like gas chromatography (GC) and liquid chromatography (LC) in the determination of lipids are discussed. Finally, the potential of CE in the determination of lipids in the future is illustrated.     

Determination of tea catechins

An overview of analytical methods for the measurement of biologically important tea catechins is presented. Liquid chromatography and capillary electrophoresis are the most cited techniques for catechin separation, identification and quantitation. Liquid chromatography with ultraviolet detection is frequently used; however, mass spectrometry, electrochemical, fluorescence and chemiluminescence detection are also utilized in cases where more sensitive or selective detection is needed. Two modes of capillary electrophoresis, capillary zone electrophoresis and micellar electrokinetic capillary chromatography, have been employed for the determination of catechins. Both modes of capillary electrophoresis are based on ultraviolet detection. Additional analytical techniques, such as gas chromatography, thin-layer chromatography, paper chromatography, spectrophotometry, biosensing, chemiluminescence and nuclear magnetic resonance spectroscopy have also been utilized for the determination of catechins and are reviewed herein.     

Cost effective,robust, and reliable coupled separation techniques for the identification and quantification of phospholipids in complex biological matrices: Application to insects

The quantification of phospholipid classes and the determination of their molecular structures are crucial in physiological and medical studies. This paper's target analytes are cell membrane phospholipids, which play an important role in the seasonal acclimation processes of poikilothermic organisms. We introduce a set of simple and cost‐effective analytical methods that enable efficient characterization and quantification of particular phospholipid classes and the identification and relative distribution of the individual phospholipid species. The analytical approach involves solid‐phase extraction and high‐performance thin‐layer chromatography, which facilitate the separation of particular lipid classes. The obtained fractions are further transesterified to fatty acid methyl esters and subjected to gas chromatography coupled to flame ionization detection, which enables the determination of the position of double bonds. Phospholipid species separation is achieved by high‐performance liquid chromatography with mass spectrometry, which gives information about the headgroup moiety and attached fatty acids. The total content of each phospholipids class is assessed by phosphorus determination by UV spectrophotometry. The simultaneous analysis of phosphorus, fatty acid residues, and phospholipid species provides detailed information about phospholipid composition. Evaluation of these coupled methods was achieved by application to an insect model, Pyrrhocoris apterus. High correlation was observed between fatty acid compositions as determined by gas chromatography and high‐performance liquid chromatography analysis.     

Determination of halogenated flame retardants by liquid chromatography coupled to mass spectrometry

We present an overview of current analytical methods for selected halogenated flame retardants (HFRs), focusing on instrumental determination using liquid chromatography coupled to mass spectrometry. We based the strategy for literature search on recent articles published in peer-reviewed scientific journals or conference proceedings. We report on selected HFRs and some metabolites and transformation products, and on the analytical performances of different ionization modes, with emphasis on selectivity and sensitivity. Moreover, we compare these parameters with those obtained by gas chromatography.     

A review of chromatographic methods for the assessment of phospholipids in biological samples

Phospholipids are important constituents of all living cell membranes. Lipidomics is a rapidly growing field that provides insight as to how specific phospholipids play roles in normal physiological and disease states. There are many analytical methods available for the qualitative and quantitative determination of phospholipids. This review provides a summary of the methods that were historically used such as thin layer chromatography, gas chromatography and high-performance liquid chromatography. In addition, an introduction to applications of interfacing these traditional chromatographic techniques with mass spectrometry is provided.     

Membrane Methods of Substance Separation in Analytical Chemistry

A review of the membrane methods of substance separation used in analytical chemistry is presented. Membrane methods based on gas-diffusion separation and dialysis extraction, membrane filtration, membrane extraction, and chromatomembrane separation are considered. The possibility of combining membrane methods with modern methods of substance determination, such as flow-injection analysis, gas and liquid chromatography, capillary electrophoresis, mass spectrometry, and so on is discussed. The list of references consists of 200 items.     

Direct analysis of alkylnaphthalenes in crude oils by two-dimensional capillary gas chromatography

Summary Diaromatics are geochemically significant constituents of crude oils. Their determination is usually achieved by elaborate prefractionation methods, such as medium pressure liquid chromatography and HPLC, prior to capillary gas chromatography. The present contribution describes the quantitative analysis of methylnaphthalenes, ethylnaphthalenes, and dimethylnaphthalenes in selected crude oils by two-dimensional capillary GC. Since the method does not comprise any work-up procedure the determination of geochemical parameters (alkylnaphthalene concentration ratios) is performed on the original, untreated crude oil samples. Accordingly, the analytical results reflect the original composition. The influence by evaporational losses in the laboratory is minimized.     

Chromatographic methods for blood alcohol determination.

This review is focused on the different chromatographic strategies for blood alcohol determination which can be adopted for clinical and/or forensic purposes. Particular attention is paid to gas chromatography and to high-performance liquid chromatography. However, other analytical techniques in common use, such as chemical and enzymic methods, are also briefly presented, together with some, at present unusual or experimental, approaches, such as enzymic reactors and catalytic electrodes, which are suitable for application in column liquid chromatography. Finally, mention is made of the methods for the determination of acetaldehyde, the major ethanol metabolite, and of some proposed markers of chronic alcohol abuse, such as acetaldehyde-protein adducts and carbohydrate-deficient transferrin. In order to give the background of knowledge for the rational choice of an analytical strategy, an updated outline of ethanol metabolism and toxicology is presented, together with basic information for the interpretation of the results. Problems concerning blood sampling and storage are also discussed.     

Analytical methods used to measure acrylamide concentrations in foods

The state-of-the-art of analysis for acrylamide in food is reviewed. The majority of analytical methods adopts a similar approach: addition of internal standard to the specimen, extraction with water, purification of extract using a solid-phase extraction cartridge, and then determination using either gas chromatography coupled to mass spectroscopy (GC/MS) after bromination, or direct measurement with liquid chromatography coupled to mass spectroscopy (LC/MS). The available methods generally show good agreement and are likely to be accurate. However, improvements in precision (within-laboratory) and repeatability (between-laboratory) are needed by particular data users.