共查询到20条相似文献,搜索用时 15 毫秒
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The newest results in the chromatographic analysis of synthetic and natural fungicides present in biological and environmental matrices are collected and critically evaluated. Examples of the employment of gas chromatography, liquid chromatographic technologies, such as thin-layer chromatography and high-performance liquid chromatographic methods as well as electrically driven systems are presented. The advantages and disasdvantages of the various chromatographic technologies are briefly discussed and the efficacies of the methodologies are compared. 相似文献
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The lipophilicity of a series of anticancer propargylthioquinoline derivatives has been investigated using chromatographic and computational methods. The parameters of relative lipophilicity (R(MO) and logk0) of the tested compounds were determined experimentally both by reversed-phase thin layer (RP-TLC), and high-performance liquid chromatographic methods (RP-HPLC, LiChrospher RP18 column), with mixtures of acetonitrile and water as mobile phases. Their phospholipophilicity (logk(0IAM)) was determined using immobilized artificial membrane HPLC (IAM. PC DD2 Regis column). Mobile phase acetonitrile concentrations were in the ranges 50-90% (RP-TLC), 55-90% (RP-HPLC) and 35-60% (IAM-HPLC). The R(M), logk and logk(IAM) values of the compounds investigated were linearly dependent on acetonitrile concentration. The analysis led to the calculation of R(MO), logk0 and logk(0IAM) parameter values for each of the tested compounds. Their partition coefficients (logP) were also calculated with the Pallas and CAChe programs. The obtained results indicated that, among experimental methods, both RP-TLC and RP-HPLC gave similar results, and these methods enable the determination of lipophilicity of derivatives of thioquinolines. Using the IAM-HPLC technique a simple method of estimation of phospholipoplilicity was described. The CAChe program might better predict calculated lipophilicity logP values, and therefore is a useful tool for the early stage of design of new propargyl thioquinolines. 相似文献
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《Separation & Purification Reviews》2013,42(1):63-89
Samples presented for chemical analysis are invariably mixtures, often very complex mixtures. This has led to the widespread acceptance and application of what have become called hyphenated chromatographic techniques. These techniques are combinations of chromatographic instrumentation with some (usually) spectroscopic technique. In this review, we treat the most important and useful of these combinations. The basic instrumental features of each method are described, and possible applications are discussed. The relative capabilities of each technique are weighed, and tradeoffs are discussed. In closing, a list of suggested further reading is provided. 相似文献
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固定化铜离子亲和膜色谱柱吸附血红蛋白的研究 总被引:2,自引:0,他引:2
将纤维素滤纸进行碱处理及环氧活化、偶联亚氨基二乙酸、固定化铜离子等处理,并将其装入自制的色谱柱管,制得固定化铜离子亲和膜色谱柱。该柱可用于吸附血红蛋白(hemoglobin,Hb),吸附率可达到90%以上。考察了上样量、pH值、温度、上样速度等因素对固定化铜离子亲和膜吸附Hb的影响。实验结果表明,固定化铜离子亲和膜色谱柱吸附血红蛋白的最佳条件为:室温下实验,缓冲体系的pH值控制在6~8,上样速度0.5~1.0 mL/min,上样量为3.16~7.90 mg/g。 相似文献
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Gillis Johansson 《Applied biochemistry and biotechnology》1982,7(1-2):99-106
The theory for analytical packed-enzyme reactors is discussed and it is shown that a 100% conversion efficiency gives many
advantages. This concept has been applied to methods for substrate determinations of urea, amino acids, and glucose. Enzyme
reactors have also been used in the effluent from a Chromatographic column to enhance selectivity and sensitivity for cholesterol.
Enzyme reactors for the determination of inhibitors, e.g. mercury ions, should be designed differently. A low conversion efficiency
gives high sensitivity and a linear response. 相似文献
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T. Kowalska 《Chromatographia》1983,17(6):315-317
Summary The possibility of comparing various chromatographic sorbents in respect of their activity is discussed utilizing a simple thermodynamic approach presented earlier. 相似文献
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Summary The universal retention index has been developed on the basis of a critical analysis of the forms of chromatographic retention data presentation. Methods are presented for the determination of the universal retention index. The advantages of the universal retention index system in the evaluation of the selectivity and classification of stationary phases and in the determination of the composition of binary and polynary stationary phases are discussed. The thermodynamic aspect of the suggested system of chromatographic retention data presentation is also considered. 相似文献
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C. Martínez Montero M.C. Rodríguez Dodero D.A. Guillén Sánchez C.G. Barroso 《Chromatographia》2004,59(1-2):15-30
This review presents a study of new advances in chromatographic methods and capillary electrophoresis for the analysis and quantification of carbohydrates in food and drink that have been made in essentially the last seven years (1995–2002). All the main groups of sugars have been considered: monosaccharides, disaccharides, trisaccharides, oligosaccharides, related compounds such as alditols, alditol glycosides, polyols, amino sugars, deoxy sugars, uronic acids and aldonic acids. The chromatographic methods referred to are High Performance Liquid Chromatography (HPLC), Gas Chromatography (GC) and related techniques (AMD-HPTLC: High Performance Thin-Layer Chromatography with Automated Multiple Development). Capillary Electrophoresis (CE) was also discussed. 相似文献
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复杂色谱信号自动解析中的化学计量学方法 总被引:1,自引:0,他引:1
色谱及其联用技术日趋完善,并向自动化、高通量和快速的方向发展。化学计量学利用"数学分离"手段,可以实现色谱信号的自动化解析,已成为现代色谱分析中非常活跃的研究领域。但以往的化学计量学方法并不能完全有效地实现复杂色谱信号自动化解析。为此,自动化色谱解析算法成为科研工作者关心的重点,众多新型的自动化解析算法被提出。针对复杂一维色谱数据以及联用仪器得到的二维和更高维数据的自动化分析,化学计量学研究主要集中在自动色谱峰识别、背景以及基线漂移校正、色谱谱峰漂移校正以及重叠色谱峰的解析。该文对近十年来发展的复杂体系色谱信号自动化解析中化学计量学方法的原理与应用进行了总结与评述,比较了各类方法的优势与不足。在此基础上,针对当前色谱自动化分析过程中的难题对未来该领域的研究方向进行了展望。 相似文献
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金属螯合亲和色谱中固定金属与蛋白质的作用 总被引:11,自引:0,他引:11
在不同PHNaCl的磷酸缓冲体系,比较了牛血清蛋白(BSA)、核糖核酸酶(RNase)、细色素C(Cyt-C)和溶菌酶(Lys)在IDA裸柱和一些金属螯合柱上的保留特性,考察了固定金属对蛋白质保留行为的影响,指出蛋白质在强结合IDA-Cu柱上的保留主要受固定金属和蛋白质间配位作用支配,在弱亲和的IDA-Ni,IDA-Co和IDA-Zn柱上的保留主要受静电作用控制,配位作用为辅,讨论了金属螯合亲和色谱中影响蛋白质和金属配位的主要因素,金属离子的电荷和半径,配位原子对中心离子外层d轨道的影响,以及蛋白质表面配位的组氨酸数目,离解常数和取向,影响金属螯合配体和蛋白质静电作用的主要因素为溶液的PH和蛋白质的等电点pI. 相似文献
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Summary After a brief recall of the chromatographic principles, the different applications of gas chromatographic measurements of
thermodynamic equilibria were reviewed. Gas and liquid chromatographies are now well known and elegant methods for measuring
the physicochemical properties and phase equilibrium thermodynamic constants. Although fundamentally a dynamical method and
mostly known as a powerful separation technique, chromatography can be schematized by a sucession of equilbria of a chemical
species partitioning between a mobile phase and a fixed liquid or solid stationary phase. It can be operated in either infinite
dilution or finite concentration conditions and permits to collect a large number of data for calculating molecular interactions
for solutes which are either rare or available at the trace level.
Gas chromatography permits the measurement of gas adsorption isotherm, gas-liquid equilibria, molecular diffusion and interaction
virials. The modelization of successive partition equuilibria occuring in the chromatographic column leads to rather simple
expression of differential enthalpy, entropy, free energy of adsorption or solution, variation of heat capacity, complexation
constant, second virial coefficients, gas-solid and gasliquid isotherm and also binary or ternary equilibria. The possibilities
of High Performance-Liquid Chromatography to investigate adsorption from solutions and chemical equilibria are also discussed. 相似文献
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胆甾型苯并-15-冠-5(简称CH-B-15-C-5)在不同温度范围内的相态不同,在同一温 度范围内因处理方式不同而物性亦相去甚远,用其作成的GC固定相兼具气固色谱(GSC)、 普通气液色谱(GLC)和冠醚液晶气液色谱(CL-GLC)多种功能。用该固定相在不同条件下对 乳酸和乳酸乙酯光学异构体混合物的分高效果进行了比较研究,并探讨了手性拆分机理。 相似文献
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Le Peng Xin Gao Long Wang Aiqiang Zhu Xiang Cai Pian Li Wenlong Li 《Electrophoresis》2022,43(18-19):1882-1898
Design of experiment (DoE) techniques have been widely used in the field of chromatographic parameters optimization as a valuable tool. A systematic literature review of the available DoE techniques applied to the development of a chromatographic analysis method is presented in this paper. First, the most common available designs and the implementation steps of DoE are comprehensively introduced. Then the studies in recent 10 years for the application of DoE techniques in various chromatographic techniques are discussed, such as capillary electrophoresis, liquid chromatography, gas chromatography, thin-layer chromatography, and high-speed countercurrent chromatography. Current problems and future outlooks are finally given to provide a certain inspiration of research in the application of DoE techniques to the different chromatographic techniques field. This review contributes to a better understanding of the DoE techniques for the efficient optimization of chromatographic analysis conditions, especially for the analysis of complex systems, such as multicomponent drugs and natural products. 相似文献
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磷脂膜色谱及其在药物跨膜转运评价中的应用 总被引:1,自引:0,他引:1
磷脂膜色谱是固态基质上的有序磷脂分子单层体系采用色谱学方法仿真药物与细胞膜相互作用过程,可用来评价药物的细胞膜渗透性和活性。硅胶表面上的磷脂单分子层模拟了单层细胞膜,因此药物的磷脂膜色谱保留行为可用于预测药物与细胞膜的相互作用。目前考察药物跨膜转运的模型主要有正辛醇/水系统、脂质体/水系统、反相色谱(ODS)以及磷脂膜色谱。与前述3种系统比较,磷脂膜色谱除了具有高效、简便等特点外,同时能模拟药物与生物膜之间疏水作用力以外的其他作用力,因此对磷脂膜色谱的研究也越来越深入。由于药物细胞膜渗透性对其有效性和安全性起着关键作用,因此磷脂膜色谱在新药研发早期阶段的介入可以有效地降低后期候选药物的淘汰率,提高新药的研发效率。该文就磷脂膜色谱的研究及在药物跨膜转运评价中的应用进行了综述。 相似文献
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Affinity monolith chromatography (AMC) is a liquid chromatographic technique that utilizes a monolithic support with a biological ligand or related binding agent to isolate, enrich, or detect a target analyte in a complex matrix. The target-specific interaction exhibited by the binding agents makes AMC attractive for the separation or detection of a wide range of compounds. This article will review the basic principles of AMC and recent developments in this field. The supports used in AMC will be discussed, including organic, inorganic, hybrid, carbohydrate, and cryogel monoliths. Schemes for attaching binding agents to these monoliths will be examined as well, such as covalent immobilization, biospecific adsorption, entrapment, molecular imprinting, and coordination methods. An overview will then be given of binding agents that have recently been used in AMC, along with their applications. These applications will include bioaffinity chromatography, immunoaffinity chromatography, immobilized metal-ion affinity chromatography, and dye-ligand or biomimetic affinity chromatography. The use of AMC in chiral separations and biointeraction studies will also be discussed. 相似文献