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1.
分子印迹技术是近年来基于分子识别的研究基础上发展起来的一种新的功能性聚合物合成技术。由于具有卓越的分子识别性能,同时具有良好的物理化学稳定性,分子印迹聚合物(MIP)在手性化合物分离、环境分析、生物模拟传感器、模拟酶催化、临床药物分析和膜分离技术等领域展现了良好的应用前景。间尼索地平药物为河北医科大学药学院首创、且具有自主知识产权的国家一类新药。  相似文献   

2.
关于分子印迹技术的研究   总被引:4,自引:0,他引:4  
分子印迹聚合物 (MIP)可在分子水平上对物质进行选择性识别 ,类似于酶和底物、抗体和抗原的关系 ,且具有生物活性物质无法比拟的稳定性 ,所以分子印迹技术引起了众多学者的关注 ,使其成为一个新兴的热门研究课题  相似文献   

3.
间尼索地平分子模板聚合物的识别特性1   总被引:1,自引:0,他引:1  
分子印迹技术是近年来基于分子识别的研究基础上发展起来的一种新的功能性聚合物合成技术.由于具有卓越的分子识别性能,同时具有良好的物理化学稳定性,分子印迹聚合物(MIP)在手性化合物分离、环境分析、生物模拟传感器、模拟酶催化、临床药物分析和膜分离技术等领域展现了良好的应用前景[1-2].间尼索地平药物为河北医科大学药学院首创、且具有自主知识产权的国家一类新药.此药物为手性对映体结构,其(R)-和(S)-间尼索地平的药效、药理、毒理作用不甚明确.为了减少给药量和对人体产生的毒副作用,必须对其进行手性拆分.本论文对间尼索地平分子模板聚合物的制备和性能识别进行了研究,旨在进一步探索分离间尼索地平的新方法.1 实验部分1.1 主要仪器与试剂  相似文献   

4.
分子印迹聚合物的设计合成   总被引:10,自引:0,他引:10  
分子印迹法是制备对特定分子(印迹分子)具有识别选择性的聚合物的技术,近年来,分子印迹法制得的聚合物在分离,分析,免疫测定,催化、模拟酶及生物传感器等方面的应用引起人们的广泛关系。本文介绍了分子印迹技术的基本原理,对分子印迹聚合物合成研究的最新进展进行了综述,评述了各种制备方法的优缺点,拽出了合成技术未来的发展方向。  相似文献   

5.
分子印迹技术是制备对特定目标分子具有分子识别性能的分子印迹聚合物的技术.分子印迹聚合物(MIP)兼备了生物识别体系和化学识别体系的优点,具有抗恶劣环境、选择性高、稳定性好、机械强度高、制备简单等特点,可选择性识别富集复杂样品中的目标物.  相似文献   

6.
分子印迹聚合物(MIP)在合成与催化方面的应用受到越来越多的关注.传统的本体聚合生成的聚合物往往具有活性中心的利用率低、活性中心不均一、底物难以到达等问题.由于纳米材料具有很高的比表面积,将MIP制备成纳米级别的材料将有可能解决这些问题.本研究的目的是在纳米材料上构建分子印迹微反应器(MIM).通过多壁碳纳米管(MWNTs)上羟基的酯化反应在碳纳米管表面枝接双键,以蒽和马来酸的加成反应产物为模板分子,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,通过微波辐射聚合在碳纳米管表面枝接一层厚度约为30 nm 的分子印迹催化剂. 该催化剂对蒽和马来酸的加成反应具有明显的催化作用,反应开始后的180min内,催化反应速率是不加催化剂反应速率的1.77倍. 催化动力学遵守Michaelis-Menten方程,催化反应最大速率(vmax)为0.713 umolL-1S-1,米氏常数(KM)为17735.24 umolL-1.  相似文献   

7.
以赤霉酸(GA3)为印迹分子,改变功能单体与致孔剂种类合成了四个分子印迹聚合物(MIP1-4)及两个分子印迹膜(MIM1-2).采用紫外光度法分别测定了印迹分子分别与功能单体丙烯酰胺(AM)和甲基丙烯酸(MAA)间的结合常数和化学计量比(n=2).平衡结合实验研究表明,以AM为单体制备的MIP1对印迹分子GA3具有更高的结合量和良好的印迹效率.膜渗透及膜过滤实验表明,以AM为单体制备的MIM1对GA3分子具有一定的选择性分离性能.  相似文献   

8.
分子印迹聚合物(MIP)是一种对目标分子(模板分子)具有选择性结合能力的聚合物.配位印迹聚合物(CIP)是基于金属离子与功能单体、模板分子间配位作用的分子印迹聚合物,既沿袭了MIP的优点,又具有适用于极性环境等优点,在食品、环境、生物、医药等领域目标物的识别中有良好的应用潜力.本文介绍了CIP的原理和特点,综述了CIP在分析化学中的应用进展,展望了CIP的发展前景.  相似文献   

9.
随着人们生活水平的逐步提高,因人体内胆固醇过高所产生的疾病呈逐年增加的趋势.近年来的研究表明,胆固醇分子印迹聚合物对胆固醇具有良好的选择性吸附能力.将胆固醇分子印迹聚合物作为胆固醇的识别剂,提取食品中的胆固醇和治疔胆固醇有关的疾病,展现出了良好的应用前景.本文分别从胆固醇分子印迹聚合物的制备方法、识别机理、提高选择性识别途径以及新的印迹方法等方面进行了综述.  相似文献   

10.
用于分子识别的分子印迹聚合物固定相   总被引:7,自引:4,他引:7  
着重介绍了分子印迹聚合物(MIP)作为一种分离介质在手性化合物拆分方面的应用,系统总结了分子印迹的原理和MIP的4种合成方法,初步探讨了MIP的分子识别机理,并阐述了它的应用以及优点和缺点。  相似文献   

11.
The ability of cyclodextrins to form inclusion complexes with hydrophobic species in aqueous solution makes them well-suited to the development of molecular reactors, to be used as miniature reaction vessels in order to control the outcomes of chemical transformations at the molecular level. In this manner, reaction rates can be increased and products may be obtained that are different to those normally accessible from reactions in free solution. Examples used to illustrate these effects include: the application of cyclodextrins to control the regioselectivity of bromination of aromatic substrates with pyridinium dichlorobromate: the use of a metallocyclodextrin to increase the rate of hydrolysis of a phosphate triester by almost five orders of magnitude; the development of modified cyclodextrins to increase the rates and reverse the regioselectivity of nitrile oxide cycloadditions ; and the use of a cyclodextrin dimer to change the ratio of formation of indigoid dyes by a factor of more than 3500.  相似文献   

12.
Many enzymes catalyze reactions with multiple chemical steps, requiring the stabilization of multiple transition states during catalysis. Such enzymes must strike a balance between the conformational reorganization required to stabilize multiple transition states of a reaction and the confines of a preorganized active site in the polypeptide tertiary structure. Here we investigate the compromise between structural reorganization during the catalytic process and preorganization of the active site for a multistep enzyme-catalyzed reaction, the hydrolysis of esters by the Ser-His-Asp/Glu catalytic triad. Quantum mechanical transition states were used to generate ensembles of geometries that can catalyze each individual step in the mechanism. These geometries are compared to each other by superpositions of catalytic atoms to find "consensus" geometries that can catalyze all steps with minimal rearrangement. These consensus geometries are found to be excellent matches for the natural active site. Preorganization is therefore found to be the major defining characteristic of the active site, and reorganizational motions often proposed to promote catalysis have been minimized. The variability of enzyme active sites observed by X-ray crystallography was also investigated empirically. A catalog of geometrical parameters relating active site residues to each other and to bound inhibitors was collected from a set of crystal structures. The crystal-structure-derived values were then compared to the ranges found in quantum mechanically optimized structures along the entire reaction coordinate. The empirical ranges are found to encompass the theoretical ranges when thermal fluctuations are taken into account. Therefore, the active sites are preorganized to a geometry that can be objectively and quantitatively defined as minimizing conformational reorganization while maintaining optimal transition state stabilization for every step during catalysis. The results provide a useful guiding principle for de novo design of enzymes with multistep mechanisms.  相似文献   

13.
记述了氧化酶在生物催化中的应用. 较之传统的化学反应, 氧化还原生物催化反应有较好的选择性、可控性和经济性, 人们正在积极地寻找这类催化剂. 自然界中被高度还原的烃类品种丰富, 因此催化烷烃末端或近末端氧合反应的酶也相对容易找到. 很多这一类的酶生化特性已作了详细的描述, 烷烃加氧酶催化高附加值反应的潜力已得到了广泛地认可.  相似文献   

14.
水相识别分子印迹技术   总被引:1,自引:0,他引:1  
在各种基于超分子方法的仿生识别体系中,分子印迹聚合物已经证明是一种有潜力的合成受体,受到了广泛的关注。传统的分子印迹技术通常是在有机溶剂中制备对小分子具有选择性的印迹聚合物,而在水相中制备及识别生物大分子的研究仍具有相当的挑战性。从小分子到生物大分子、从有机相到水相,反映了分子印迹技术的发展趋势。本文对最近几年分子印迹在水相制备与识别方面的最新进展进行了总结与评述,探讨了水相识别印迹聚合物的设计策略与制备方法;着重介绍了水相识别技术在固相萃取、色谱固定相、药物控释、中药有效成份提取以及生物分子识别等方面的应用;指出了提高水相识别选择性的途径并对其将来的发展进行了建议与展望。  相似文献   

15.
The use of molecular beams to study chemical dynamics at surfaces is outlined. The techniques is briefly introduced and its applications are given in a few areas. Scattering experiments give detailed information about the first steps toward a chemical reaction at a surface. Beams with enhanced population of specific quantum states make an even more detailed analysis possible. Adsorption at surfaces can be studied very well using beam methods, especially in the case of activated processes. Beams can be used to grow novel structures. Beams allow the study of chemical reactions at surfaces, and in particular those where product are directly ejected into the gas phase, or where reactions take place upon impact. Finally the study of liquid surfaces is briefly introduced.  相似文献   

16.
There has recently been a revival of interest in microbial biochemistry. Part of this resurgence is due to the increased presence of man-made organic compounds in the biosphere and the resultant interest in microorganisms which can degrade these xenobiotic molecules. Also, advances in genetic engineering have raised the possibility of utilizing the chemical machinery of bacteria for commercial profit and social benefit. The Baeyer-Villiger reaction is a useful transformation in organic synthesis which provides chemists with a gentle means of converting ketones into esters or lactones. The reaction, however, suffers from the problems of low yield and the need, in some cases, to utilize harsh conditions. There exist bacteria, capable of growth on aliphatic molecules, that contain enzymes which can catalyze Baeyer-Villiger reactions. These enzymes, known as monooxygenases, are involved in the breakdown of acyclic and alicyclic ketones to provide simpler carbon units for further catabolism. The gamut of reactions catalyzed by some of these enzymes is remarkable. This diversity, plus their availability in pure form in quantity by genetic engineering raises the possibility that these biocatalysts can be useful as reagents in organic synthesis.  相似文献   

17.
Experimental studies on reaction dynamics by use of molecular beams and oriented molecular beams are reviewed in order for looking closer to chemical reactions as well as photodissociations at the molecular level. We discuss about versatility and usefulness of the electrostatic hexapole sate‐selector as a non‐destructive selector for molecular structure analysis. Some experimental evidences on novel reaction dynamics in photodissociation and stereodynamics are presented followed by concluding remarks and future perspectives for controlling chemical reactions from the point of view of green chemistry, by manipulating molecular orientation without any catalyst nor by applying any external forces like intense electromagnetic field.  相似文献   

18.
We discuss the use of tunneling electron current to control and catalyze chemical reactions. Assuming the separation of time scales for electronic and nuclear dynamics we employ Langevin equation for a reaction coordinate. The Langevin equation contains nonconservative current-induced forces and gives nonequilibrium, effective potential energy surface for current-carrying molecular systems. The current-induced forces are computed via Keldysh nonequilibrium Green's functions. Once a nonequilibrium, current-depended potential energy surface is defined, the chemical reaction is modeled as an escape of a Brownian particle from the potential well. We demonstrate that the barrier between the reactant and the product states can be controlled by the bias voltage. When the molecule is asymmetrically coupled to the electrodes, the reaction can be catalyzed or stopped depending on the polarity of the tunneling current.  相似文献   

19.
张亚 《化学通报》2022,85(1):3-13
化学反应会受其所处微环境影响,因此不同分子间相互作用对反应进程的调控不容忽视.水溶液作为优良的反应介质,其应用常受到反应物溶解性差的限制.在水溶液中引入胶束或囊泡等两亲分子组装,可在一定程度上克服这种不足.这些均匀分散的动态组装,提供了有别于本体水溶液的微环境,以非共价的方式,将单体结合到其极性表面或疏水内核.通过加速...  相似文献   

20.
基于硅胶表面修饰的分子印迹技术研究进展   总被引:5,自引:1,他引:4  
徐伟箭  项伟中  周晓  徐丰 《应用化学》2003,20(10):919-0
综述;基于硅胶表面修饰的分子印迹技术研究进展  相似文献   

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