中药物质基础的高效液相色谱分离分析方法研究

高效液相色谱方法已成为中药物质基础研究的重要手段．在中药质量控制、中药标准品制备、活性化合物发现等方面发挥着不可替代的作用．然而我们的实验数据表明,一个中药材可能包含上万个化合物．中药物质基础的复杂性对高效液相色谱方法提出了巨大挑战．本文针对液相色谱方法在中药物质基础分离分析中存在的问题与难点,结合红花、黄连、姜黄三味药材样品,从亲水色谱分离模式、新型色谱固定相、二维液相色谱分离系统和液相色谱质谱联用技术等方面讨论了液相色谱的分离分析方法和发展方向．结果表明,高效液相色谱新技术新方法在中药复杂体系的分离分析中具有很大的发展潜力和应用前景．     

在线二维液相色谱技术在中药研究中的应用进展

中药的组成复杂,其化学成分的表征和识别一直是中药研究的基础和关键。在线二维液相色谱是基于两种分离模式构建的色谱分析技术,主要包括中心切割二维液相色谱和全二维液相色谱两种模式,因二者具有更高的峰容量而在中药研究中备受青睐。该文对在线二维液相色谱技术的概念和特点进行了讨论,并对二维液相色谱在中药研究中的应用进行了综述,以期为该技术在中药质量控制、物质基础表征、活性成分筛选等研究方面提供一定参考。     

色谱最新研究亮点

1 多维分离技术新进展 一维色谱是目前最常用的分离分析方法,然而对于复杂体系如蛋白质组,采用一维分离模式其分离度远远不能满足要求.Giddings理论告诉我们:对于分离机理相互正交的二维分离系统(如色谱),峰的容量应该为两个色谱柱峰容量的乘积.因此,多维分离系统是解决复杂分离体系的一个最佳选择.在多维色谱中二维气相色谱发展较快,目前全二维气相色谱仪业已商品化,其峰的容量达到104以上.而二维液相色谱,尤其是正相/反相二维液相色谱技术发展较为缓慢,其主要的技术瓶颈在于第一维色谱(正相)分离后的流动相严重干扰第二维色谱(反相)的分离.     

生物碱的高效液相色谱分离分析与纯化制备研究进展

生物碱是天然产物中药用活性较好的一类化合物,在分离科学与技术领域,生物碱的分离一直是一个研究热点和难点问题。近年来,随着高效液相色谱填料和分离方法的发展,生物碱的分离分析和纯化制备有了长足的进步。该文主要针对碱性化合物的峰形拖尾问题,综述了高效液相色谱理论的发展和色谱分离技术的进步,以及近年来新型色谱填料和分离方法在生物碱分离分析和纯化制备中的应用,并对其前景进行了展望。     

生物制药研究中的多维色谱

对全二维气相色谱(GC×GC)、全二维液相色谱(HPLC×HPLC)、多维毛细管电泳等多维分离技术在生物制药研究中的应用进行了综述,其中对作者所在研究组在全二维气相色谱应用于中药及固相萃取-液相色谱联用分析系统等方面的工作做了重点介绍。由所综述的生物制药研究得出结论：多维分离方法以其高分辨、快速、自动化等特点已经在生物制药领域显示出它的巨大优势,并将发挥更大的作用。     

二维色谱技术及其在中药领域中的应用

二维色谱是近年发展起来的多维色谱分离技术,因其高分辨率、高峰容量、高灵敏度等优点,在复杂样品的分离分析中发挥了巨大作用．中药是一个复杂的化学体系,包含多种类化学成分,因此,分析和阐明中药中的化学成分是中药现代研究的一个关键问题．二维色谱技术在中药等复杂体系的应用中显示了重要的应用价值,也具有广阔的发展前景．本文对二维色谱的分类、主要部件以及在中药领域中的应用进行综述,重点介绍二维气相色谱和二维液相色谱在中药研究中的应用．     

反相液相色谱对多肽的分离、纯化与制备

用反相高效液相色谱（RPLC）对两种化学合成多肽－－32肽和21肽进行了分离、纯化和制备。在用分析型RPLC色谱柱对多肽样品的制备过程中，对其进样量和洗脱梯度进行了选择。每次进样量为5mg，在最优化色谱条件下，用RPLC一步就可对21肽进行分离纯化，其纯度达到98.6%。而32肽由于样品组分更加复杂，RPLC一步纯化后其纯度仅有80％。通过对色谱分离条件的再次优化，对32肽进行二次分离纯化，纯度达杂，RPLC一步纯化后其纯度仅有80％。通过对色谱分离条件的再次优化，对32肽进行二次分离纯化，纯度达到96.4%。在其最优化条件下，通过多次样品收集和冷冻干燥，分别制备了高纯度的21肽和32肽各100mg。     

多维液相柱色谱

多维液相柱色谱分离分析复杂样品越来越受到重视。本文介绍了国内外多维液相柱色谱的近期发展,详细讨论了二维液相色谱的实现,其中包括固定相、流动相的选择、温度变量的作用以及两维间切换的实现,并对多维液相柱色谱的应用现状进行了总结。     

反相液相制备色谱法结合超临界流体制备色谱法分离纯化海风藤中的化合物

建立了基于反相液相制备色谱和超临界流体制备色谱的组合方法,用于分离纯化醇提水沉后石油醚层中的海风藤。首先以甲醇作为改性剂,采用醇提水沉法去除海风藤甲醇提取物中的叶绿素,加入硅藻土后用石油醚回流富集目标成分。选用反相C18制备色谱柱将其分为18个组分,然后将组分在SFC模式下进行制备。选用酰胺色谱柱,以甲醇为改性剂,在柱温30℃、背压15.0 MPa的条件下进行分离。基于反相色谱和超临界流体色谱不同的分离选择性,最后分离得到6个高纯度化合物。该法展示了反相制备色谱和超临界流体制备色谱在海风藤分离纯化方面的优势,特别是超临界流体色谱在天然产物的分析和制备方面的巨大潜力。     

在线单柱二维液相色谱法对蛋清中三种活性蛋白的快速分离纯化

基于一种新型的强阳离子交换/疏水色谱(SCX/HIC)双功能色谱柱构建了在线单柱二维液相色谱(2DLC-1C), 分离系统实现了自动控制, 可在线进行样品收集、二维进样和二维色谱分离. 采用SCX-HIC 2DLC-1C, 在120 min内可将8种标准蛋白完全分离, 并成功应用于鸡蛋清中三种活性蛋白质的分离纯化. 结果表明利用在线2DLC-1C技术可在70 min内完成对鸡蛋清中溶菌酶、卵清蛋白和卵转铁蛋白三种活性蛋白的快速分离纯化, 其纯度分别为95%、93%和97%. 该方法减少了样品的处理步骤, 对样品的污染小, 纯化速度快, 操作简单, 易于实现自动化和放大, 对活性蛋白的快速分离制备和工业化生产具有广阔的应用前景.     

快速色谱

基于柱液相色谱和薄层色谱之间的关系,讨论如何为快速色谱选择流动相,并介绍此技术手工操作的步骤.     

Extraction chromatography of common anions in liquid-liquid anion exchange systems. Part. III. Monobasic aliphatic organic acids and their sodium salts as eluants

Summary The chromatographic behaviour of anions on paper strips treated with tri-n-octylamine (TOA) salts or Aliquat 336 and developed with aqueous solutions of acetic, formic, monochloroacetic or trifluoroacetic acids and their sodium salts was investigated. Liquid-liquid extraction of organic acids by 0.1 M solution of TOA in benzene as well as the anion exchange between benzene solutions of TOA salts or Aliquat 336 (in acetate form) in benzene and aqueous solutions of sodium halides was also studied. It was found that extraction increases in the following order of the acids: CH₃COOOH<HCOOH<CH₂CICOOH<CF₃COOH; the relative affinity of organic anions to the quaternary alkyl-ammonium cation also increase in a similar order. The extraction of acid in excess over the amount necessary to neutralize the amine was observed for all four acids. The R_F values of anions investigated depend markedly on the type of organic acids or their salts and their concentration in the mobile phase. Halide ions are more strongly retained on paper treated with Aliquat 336 as compared with TOA salts. The chromatographic systems investigated offer many possibilities to separate various anion mixtures.Parts and II: refs. [1, 2].     

A review of advances in two-dimensional thin-layer chromatography

Although there are many simple thin-layer chromatography (TLC) separations, many more are complex and involve more than a few components, that means having to use special high-performance TLC (HPTLC) plates or microspotting or banding devices to increase its resolving power if developing in only one direction. However, adding a second development to perform two-dimensional TLC (2D TLC) allows even better resolution of complex samples. This is because different modes of chromatography are being invoked by the use of one stationary phase with two mobile phases, bilayer plates, graft TLC, or multidimensional TLC. This paper is a review of recent applications that have benefitted from using 2D TLC in its various forms. They were chosen for their variety of sample types as well as the unique choices of plates and/or mobile phases made by the researchers to yield improved separations.     

Unified chromatography: Fundamentals,instrumentation and applications†

The concept of unified chromatography has been in existence for 50 years after the work of Giddings proposing that all modes of chromatography (gas chromatography, liquid chromatography, supercritical fluid chromatography and so on) may be treated together under a single unified theory. His idea was partially fulfilled 23 years later by Ishii, Takeuchi and colleagues, who demonstrated for the first time the possibility to analyze a complex sample containing substances with a wide range of boiling points and polarities in the same instrument and column, just by varying the mobile phase pressure and temperature to change from one chromatographic mode to another. This approach has been demonstrated through application to the separation of complex mixtures in several areas including crude oil, edible oils and polymers. Still, unified chromatography has not yet been fully developed. In the present work, we will review the fundamentals, instrumentation and several applications of the technique. Also discussed are the drawbacks that still hinder development, as well as the recent developments and trends in instrumentation and columns that suggest the most feasible ways forward to the full development of unified chromatography.     

TLC as a pilot technique for the optimization of gradient HPLC II. Use of data obtained from RP-18 plates for the prediction of gradient programs in reversed-phase liquid chromatography

Summary A method is described and experimentally verified permitting the determination of the optimal gradient programs in HPLC on the basis of isocratic TLC data. The proposed method has many advantages and can also be used in reversed-phase systems. A satisfactory agreement between the theoretical and experimental of V_R/V_O values has been confirmed. Some discrepancies for more strongly retained solutes are, probably due to the respective equilibrium and nonequilibrium state of the column in isocratic and gradient elution.Part I: Ref. [1].     

Exhibition of the first gas chromatographic work of Erika Cremer and Fritz Prior

Summary In November 1995, theDeutsches Museum, the world's largest technical museum, opened a new branch in Bonn, devoted to achievements after 1945. There, the first gas chromatographic system used by Erika Cremer and Fritz Prior, in 1945–47, in Innsbruck, is exhibited. The new display is described and the early activities of Erika Cremer and her students are summarized.     

Affinity monolith chromatography: A review of general principles and recent developments

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.     

茶多酚的色谱分析法

 对茶多酚的主要成分――儿茶素的色谱分析法进行了综述。重点介绍了应用最多的反相高 效液相色谱法,同时简述了平板色谱法、气相色谱法以及目前出现的新的色谱分析方法。