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催化荧光分析法研究进展及应用 总被引:1,自引:0,他引:1
评述催化荧光分析法的发展及其应用。催化荧光分析法的主要研究进展包括:新体系的发现与新试剂的合成,增效试剂的应用,流动注射技术与催化荧光分析法的结合,活化剂与抑制剂的应用。介绍了催化荧光分析法在测定无机物、有机物和酶等方面的实际应用。 相似文献
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重要生物标志物例如碱性磷酸酶(ALP)的高灵敏度检测和准确分析对于疾病的早期检测和治疗至关重要.本工作合成了Cu基金属有机框架材料HKUST-1,探索了其类氧化酶性质.通过设计HKUST-1模拟酶与ALP天然酶的级联催化体系,构建了高灵敏度及高选择性的荧光/紫外双模式检测平台,用于生物标志物ALP及焦磷酸根离子(PPi)的检测.利用所设计的级联催化反应对信号的有效放大以及荧光和紫外双信号输出,对ALP的检测限分别低至0.0078和0.039 nmol·L-1.本工作首次开发了基于模拟酶-天然酶级联催化放大的双模式生物分析方法,实现了两种生物标志物的灵敏检测以及酶抑制剂的抑制效率评估,并将其应用到人血清样品中ALP的超灵敏分析,在临床诊断中具有巨大应用潜力. 相似文献
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本文归纳了流动注射示差动力学分析法所基于的化学反应和常用的流路,评述了流动注射示差动力学分析法在单一组分的高选择性测定和多组分的连续或同时测定中的应用。 相似文献
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Guilbault等曾捉及利用Cd(Ⅱ)对酶催化非荧光物质高香草酸氧化为强荧光化合物反应的抑制作用可测定镉,但迄今尚未见利用催化动力学荧光分析法测定痕量镉的报道,本文拟利用Cd(Ⅱ)和咪唑对Co(Ⅲ)-T(4-SP)P络合物生成反应的催化作用,建立痕量镉的催化动力学荧光分析法。 相似文献
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设计和发展简便、高灵敏、高选择性的分析手段以检测低浓度急性心肌梗死生物标志物是目前临床诊断迫切的需求。电化学发光分析法由于具有稳定性好、灵敏度高、线性范围宽及可控性强等优点,能有效地进行低浓度样品检测。该方法与生物传感技术相结合,有利于实现生物体液等复杂样品中极低含量急性心肌梗死生物标志物的快速检测。本文综述了电化学发光生物传感技术在快速检测心肌梗死标志物中近5年的进展,介绍了电化学发光探针和共反应物,以及多组分生物传感检测技术等,并对其在心肌梗死标志物分析中的应用进行了总结。 相似文献
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综述了农产品中重金属的检测方法如光谱分析法(包括原子吸收光谱法、电感耦合等离子体原子发射光谱法、原子荧光光谱法和X射线荧光光谱法)、色谱分析法、电化学分析法和快速检测方法(包括酶联免疫吸附法、生物传感器法、酶抑制法、试纸和试剂比色法)的研究进展,并对其发展前景进行了展望(引用文献83篇)。 相似文献
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4-甲基伞形酮磷酸酯(4-MUP)是一类重要的荧光底物, 由于具有较高的疏水性, 荧光信号易在液滴间扩散而限制了其在液滴微流控芯片领域中的应用. 本文首先通过修饰7-羟基香豆素-4-乙酸, 制备了具有较高水溶性的新型底物分子7-二羟基磷酸酯香豆素-4-乙酸甲酯; 进而以7-二羟基磷酸酯香豆素-4-乙酸甲酯为底物, 以球刷酶(荷载大量碱性磷酸酶的聚电解质纳米颗粒, SP-AKP)为模式酶, 建立了基于液滴微流控的单SP-AKP数字式检测体系. 结果表明, 该水溶性香豆素荧光底物具有与传统4-MUP底物相似的荧光光谱和酶催化性能. 传统4-MUP酶促荧光产物5 min即在液滴中发生明显扩散, 而该水溶性香豆素荧光底物酶催化后产生的荧光产物7-羟基香豆素-4-乙酸甲酯在24 h后仍未观察到明显扩散现象, 具有优异的抑制荧光扩散性能. 在基于液滴微流控芯片的单SP-AKP数字式检测中, 对SP-AKP的检测限可达29.9 amol/L, 同时有效提升了检测时间的可操作性与数字式信号读取的准确性. 新型水溶性香豆素荧光底物有望替代4-MUP应用于以基于液滴数字式超敏生物检测为代表, 在液滴分区实现酶促反应进行超灵敏检测的众多检测领域中. 相似文献
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One‐Pot Consecutive Catalysis by Integrating Organometallic Catalysis with Organocatalysis 下载免费PDF全文
The present study integrates two types of catalysis, namely, organometallic catalysis and organocatalysis in one reaction pot. In this process, the product of the first catalytic cycle acts as catalytic component for next catalytic cycle. The abnormal N‐heterocyclic carbene–copper‐based organometallic catalyst acts as an efficient catalyst for a click reaction to provide triazole, which, in turn, acts as an efficient organocatalyst for different organic transformations, for example, aza‐Michael addition and multicomponent reactions, in a consecutive fashion in the same reaction pot. 相似文献
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Limonoid bitterness is a serious problem in the citrus industry worldwide. Limonoid glucosyltransferase is an enzyme that catalyzes the conversion of bitter limonoid into non-bitter limonoid glucoside while retaining the health benefit of limonoids in the juice. The immobilization of this enzyme in a column can solve the juice bitterness problem. More information about the catalytic residues of the en-zyme is needed in this immobilization process. Glutamate/aspartate, histidine, lysine, tryptophan, serine, and cysteine residues were chemi-cally modified to investigate their roles in the catalytic function of limonoid glucosyltransferase. Inactivation of the enzyme following modi-fication of carboxyl and imidazole moieties was a consequence of a loss in substrate binding and catalysis in the glucosyltransfer reaction. The modification of a single histidine residue completely destroyed the ability of limonoid glucosyltransferase to transfer the D-glucopyranosyl unit. Tryptophan seemed to have some role in maintaining the active conformation of the catalytic site. Lysine also seemed to have some direct or indirect role in this catalysis but the modification of serine and cysteine did not have any effect on catalysis. There-fore, we conclude that the carboxyl and imidazole groups contain amino acids are responsible for the catalytic action of the enzyme. 相似文献
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Multicomponent reactions (MCRs) receive increasing attention because they address both diversity and complexity in organic synthesis. Thus, in principle diverse sets of relatively complex structures can be generated from simple starting materials in a single reaction step. The ever increasing need for optically pure compounds for pharmaceutical and agricultural applications as well as for catalysis promotes the development of asymmetric multicomponent reactions. In recent years, asymmetric multicomponent reactions have been applied to the total synthesis of various enantiopure natural products and commercial drugs, reducing the number of required reaction steps significantly. Although many developments in diastereoselective MCRs have been reported, the field of catalytic enantioselective MCRs has just started to blossom. This critical review describes developments in both diastereoselective and catalytic enantioselective multicomponent reactions since 2004. Significantly broadened scopes, new techniques, more environmentally benign methods and entirely novel MCRs reflect the increasingly inventive paths that synthetic chemist follow in this field. Until recently, enantioselective transition metal-catalyzed MCRs represented the majority of catalytic enantioselective MCRs. However, metal contamination is highly undesirable for drug synthesis. The emergence of organocatalysis greatly influences the quest for new asymmetric MCRs. 相似文献
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The catalytic efficiency of mixed Cu(I)-Cu(II) system in situ generated by partial reduction of CuSO(4) with glucose in ethanol (nonanhydrous) under open air has been explored. With this catalysis, the multicomponent cascade reaction of A(3)-coupling of heterocyclic amidine with aldehyde and alkyne, 5-exo-dig cycloisomerization, and prototropic shift has afforded an efficient and eco-friendly synthesis of therapeutically important versatile N-fused imidazoles. Diverse heterocyclic amidines, several of which are known to be poorly reactive, and aldehydes are compatible in this catalytic process. 相似文献
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Dendrimers, the aesthetically beautiful macromolecules displaying a variety of potentially useful architecture‐induced properties, are traditionally assembled in solution. However, since 1988, a number of dendritic structures have been assembled on insoluble organic and inorganic polymers, and thus dendronized supports have been formed. One of the major applications of these new materials is in the field of heterogeneous catalysis. Supported dendritic catalytic systems, bearing the catalytic units on the dendron periphery, have been examined in the last 5 years in such reactions as hydroformylation, Heck and other Pd‐catalyzed C? C bond formations, oxidation, and enantioselective addition to aldehydes. In the majority of these studies, substantial dendritic effects on the reactivity, selectivity, or recyclability of the catalysts were observed. Although a number of factors have been suggested as sources of the effects, it is most likely that the phenomenon has a multicomponent origin. Additional research, including a full determination of the effects and their causes, is likely to lead to markedly better heterogeneous catalytic systems. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 235–262, 2005 相似文献
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H. Huang Y. Yao Q. Lin J. Zhao C. Hua X. Gou 《Russian Journal of General Chemistry》2016,86(4):934-938
Xanthene derivatives were synthesized by a multicomponent one-pot reaction of aromatic aldehydes, β-naphthol, and 5,5-dimethylcyclohexane-1,3-dione or 1,3-cyclohexanedione upon efficient and eco-friendly catalysis of Fe(III) tetranitrophthalocyanine immobilized on activated carbon in ethanol. The method tolerated a variety of functional groups and the process was carried out under mild conditions to give high yield of products (85–91%) in 30 min. The catalyst can be recycled without any loss in catalytic activity. 相似文献
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Bibliometric and thematic analyses were performed for more than 11 thousand reviews and monographs in catalysis registered in the Chemical Abstracts Plus database on the SciFinder platform from April, 2011, to December, 2012, with the aim to elucidate the hot spots of this area. The identified spots include photo- and electrocatalysis; stereoselective (bio-) catalysis; catalytic functionalization of organic compounds; catalysis by nanostructured, in particular, graphene-based materials; catalytic production of biofuel; and application of catalysis in novel energy technologies. 相似文献
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Prashasti Kumar Pratul K. Agarwal M. Brett Waddell Tanja Mittag Engin H. Serpersu Matthew J. Cuneo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16406-16412
The position, bonding and dynamics of hydrogen atoms in the catalytic centers of proteins are essential for catalysis. The role of short hydrogen bonds in catalysis has remained highly debated and led to establishment of several distinctive geometrical arrangements of hydrogen atoms vis‐à‐vis the heavier donor and acceptor counterparts, that is, low‐barrier, single‐well or short canonical hydrogen bonds. Here we demonstrate how the position of a hydrogen atom in the catalytic triad of an aminoglycoside inactivating enzyme leads to a thirty‐fold increase in catalytic turnover. A low‐barrier hydrogen bond is present in the enzyme active site for the substrates that are turned over the best, whereas a canonical hydrogen bond is found with the least preferred substrate. This is the first comparison of these hydrogen bonds involving an identical catalytic network, while directly demonstrating how active site electrostatics adapt to the electronic nature of substrates to tune catalysis. 相似文献