膜亲和色谱的现状、发展和应用

文章对膜亲和色谱的原理、特点、设备、过程和发展情况做了介绍，并对亲和膜在整个膜分离技术中的地位、所占的比重及市场预测做了述评，对膜亲和色谱与其它色谱分离技术的优缺点进行了比较。重点介绍了制备亲和膜的材料，活化方法，间隔臂和配基的种类、选择和共价键合方法，配基和配合物产生亲和作用的机理及解离过程和方法。并对膜亲和色谱在酶、蛋白质、核糖核酸等生物大分子纯化分离方面的应用情况做了述评。     

亲和膜色谱技术研究进展

对一种崭新的生物大分子分离技术－－亲和膜色谱技术做了全面的评述,介绍了亲和膜色谱分离的过程,评价了亲和膜基质材料活化、改性方法、给出了配基间隔臂的选择原则,概括了亲和膜色谱理论研究的进展,并对亲和膜色谱技术进行了展望。     

亲和色谱仿生配基的筛选和设计

利用选择性好、稳定性高、价格低廉的仿生配基作为亲和色谱的功能基团,实现对目的蛋白质的亲和分离,可以弥补常规的单克隆抗体和其他天然蛋白质配基在价格、稳定性方面的不足,从而拓展亲和色谱技术的应用范围。本文综述了亲和色谱仿生配基在筛选和设计方面的研究进展,重点介绍了组合方法和基于结构的仿生配基的设计及其应用。     

亲和膜色谱

亲和膜色谱又称亲和膜分离，其在蛋白质的分离纯化中作为一种综合性的技术出现在80年代末。亲和膜色谱主要优点是克服了颗粒状多孔载体扩散传质阻力大的缺点，代之以对流传质，这样就可以在较低的操作压和较高的流速下对目标蛋白进行快速的分离和纯化，从而缩短操作时间、提高纯化效率。本文将就近年来亲和膜色谱及其在蛋白质分离和纯化中的应用作一综述性介绍。     

以寡聚组氨酸为配基的高效亲和色谱研究

亲和色谱在所有色谱分离中选择性最高.以组氨酸为配基的亲和介质(Affinitymedia)对免疫球蛋白IgG具有亲和力,显示了良好的分离效果[1];以组氨酸为配基的亲和色谱分离纯化IgG的机理[2]以及组氨酸亲和色谱分离IgG亚基也已有报道[3].组氨酸配基亲和色谱法具有简单、有效和价廉等特点,在免疫化学、临床分析及血液制品的生产等方面均有良好的应用前景.本文分别以含1,3,5个组氨酸残基的小肽为配基,合成了系列亲和介质,并对其亲和色谱行为进行了评价,研究了不同链长的寡聚组氨酸与IgG的亲和相互作用.1　实验部分1.1　固相肽合成　采用Fmoc肽合…     

亲和色谱法的进展

概述了亲和色谱法分离机理、色谱填料及其应用的新进展,着重介绍了亲和固定相中配基发掘的新途径。全文包括66篇文献。     

染料膜亲和色谱法中膜堆的制备及应用

将染料亲和配基偶联于大孔纤维素膜上,所得亲和膜用胶粘法制成亲和膜堆,膜堆的通透性远优于通常的亲和色谱柱。装有蓝色和红色亲和膜的膜堆可分别用于人血清白蛋白和碱性磷酸酯酶的分离纯化,其中碱性磷酸酯酶可在一步操作后纯化４０倍。     

分离尿激酶的胍基型亲和色谱填料研究

尿激酶的精制一般使用亲和色谱法［’－‘ｊ．目前实际使用和文献报道最多的填料是在 ＳｅＰｈａｒｏｓｅ上键合对氨基苯眯（ｐ－ＡＢＺ）制得的［‘ｊ．这种填料分高效果较好,但机械强度不高,只能用于常压色谱,而且寿命较短．前文［‘１报道了用 ＳｅＰｈａｒｏｓｅ和聚甲基丙烯酸环氧丙酯微球为基质, Ｐ－ＡＢＺ为配基分离尿激酶的亲和色谱填料的对照研究．本文报道以含肥基的有机小分子为配基,ＳｅＰｈａｒｏｓｅ及两种聚甲基丙烯酸环氧丙酯微球为基质的分离尿激酶色谱填料的合成和性能试验．发现肥基己酸和精氨酸为配基的亲和色谱…     

从组合化学肽库中筛选亲和配基

在亲和色谱研究中 ,建立适合于某种分离对象的亲和色谱体系的关键是寻找适合的亲和配基 .小肽亲和配基具有性质稳定、合成简单、价格低及生物相容性好等特点[1] ,但这类配基也存在着亲和力弱或选择性低的缺点 .因此 ,如何寻找小肽配基以及如何提高小肽配基的亲和力和选择性的问题引起了人们的关注与重视 [1～ 3 ] .组合化学法是一种快速制备大量相关或同类化合物的革新性的方法 [4 ] ,组合肽库包括噬菌体展示肽库和合成肽库 ,这两类肽库均可用于小肽配基的筛选与优化 [1,5] .组合化学法尽管有效 ,但以小肽为目的物进行筛选时 ,往往因肽 -肽…     

亲和色谱纯化超螺旋质粒DNA的研究进展

非病毒载体质粒DNA已被广泛应用于基因治疗和DNA疫苗,目前迫切需要开发其大规模制备和分离纯化方法。亲和色谱是一种高分辨率、高选择性的分离技术,在蛋白质、抗体、核酸等生物大分子的分离纯化方面显示了良好的应用前景。本文综述了亲和色谱技术在超螺旋质粒DNA分离纯化中的研究进展,总结了各种亲和色谱方法分离超螺旋质粒DNA的机理和优缺点,并展望了亲和纯化技术在质粒DNA生产和制备中的应用前景。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.