共查询到20条相似文献,搜索用时 0 毫秒
1.
Electrochemical Signal Tracing by Glucose Oxidase and Ferrocene Dually Functionalized Gold Nanoprobe for Ultrasensitive Immunoassay
下载免费PDF全文
![点击此处可从《Electroanalysis》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A glucose oxidase (GOD) and ferrocene (Fc) dually functionalized gold nanoprobe was simply prepared for electrochemical immunoassay. By combination with sandwich immunoreaction at a carbon nanotube (CNT)‐based immunosensor and signal tracing of the nanoprobe through the Fc‐mediated GOD‐catalytic reaction, a new electrochemical immunoassay method was successfully developed. Both the multi‐enzyme signal amplification of the nanoprobe and the electron transfer promotion of the CNTs modified on the immunosensor greatly enhanced the signal response. Thus this method showed excellent analytical performance including ultrahigh sensitivity, wide linear range as well as good specificity, reproducibility, stability and reliability for human IgG measurement. 相似文献
2.
A simple flavin-based catalytic system is able to transform light into chemical output with amplified response utilizing a Cu(I)-catalyzed cycloaddition reaction. 相似文献
3.
Gold catalysis 总被引:1,自引:0,他引:1
Catalysis by gold has rapidly become a hot topic in chemistry, with a new discovery being made almost every week. Gold is equally effective as a heterogeneous or a homogeneous catalyst and in this Review we attempt to marry these two facets to demonstrate this new found and general efficacy of gold. The latest discoveries are placed within a historical context, but the main thrust is to highlight the new catalytic possibilities that gold-catalyzed reactions currently offer the synthetic chemist, in particular in redox reactions and nucleophilic additions to pi systems. Indeed gold has proved to be an effective catalyst for many reactions for which a catalyst had not been previously identified, and many new discoveries are still expected. 相似文献
4.
5.
6.
U Lüning 《Angewandte Chemie (International ed. in English)》2012,51(33):8163-8165
On/off catalysts: Control over catalysis can be gained when the catalysts can be switched between an active and a nonactive state by external stimuli. In recent examples, orthogonal signals-light, pH, or the addition of ions-are used for the switching. 相似文献
7.
In the last few years, visible-light initiated organic transformations have attracted increasing attention. The development of visible-light-promoted photocatalytic reactions, which enable rapid and efficient synthesis of fine chemicals, is highly desirable from the viewpoint of cost, safety, availability, and environmental friendliness. In this Minireview, recent advances made in this fast developing area of research are discussed. 相似文献
8.
9.
10.
Dorina Chambre Maria-Raluca Szabo C. Popescu Cornelia Idiţoiu 《Journal of Thermal Analysis and Calorimetry》2008,94(2):417-420
Using a micro-calorimetrical DSC we have compared the acid-catalyzed inversion of sucrose in homogeneous and heterogeneous
systems. Acetic acid was chosen as catalyst for homogeneous system, and several carboxylic cationites were used as heterogeneous
catalysts. The kinetic apparent parameters (A, E, k
ap) for all the systems were calculated from DSC data with Friedmann’s method and catalytic constant, k323cat, was further inferred. We found that the specific catalyst efficiency, q
cat, in heterogeneous system is over 5000 times higher than in case of homogeneous ones. The activity of heterogeneous carboxylic
systems is still about 30 times larger than those of a strong mineral acid in homogeneous catalysis.
The results indicate the high efficiency of heterogeneous systems for soft acid catalysis of the sucrose hydrolysis. 相似文献
11.
Molnar F Luinstra GA Allmendinger M Rieger B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(6):1273-1280
Carbonylation of epoxides with a combination of Lewis acids and cobalt carbonyls was studied by both theoretical and experimental methods. Only multisite catalysis opens a low-energy pathway for trans opening of oxirane rings. This ring-opening reaction is not easily achieved with a single-site metal catalyst due to structural and thermodynamic constraints. The overall reaction pathway includes epoxide ring opening, which requires both a Lewis acid and a tetracarbonylcobaltate nucleophile, yielding a cobalt alkyl-alkoxy-Lewis acid moiety. After CO insertion into the Co-C(alkyl) bond, lactone formation results from a nucleophilic attack of the alkoxy Lewis acid entity on the acylium carbon atom. A theoretical study indicates a marked influence of the Lewis acid on both ring-opening and lactone-formation steps, but not on carbonylation. Strong Lewis acids induce fast ring opening, but slow lactone formation, and visa versa: a good balance of Lewis acidity would give the fastest catalytic cycle as all steps have low barriers. Experimentally, carbonylation of propylene oxide to beta-butyrolactone was monitored by online ATR-IR techniques with a mixture of tetracarbonylcobaltate and Lewis acids, namely BF(3), Me(3)Al, Et(2)Al(+).diglyme, and a combination of Me(3)Al/dicobaltoctacarbonyl. We found that the last two mixtures are extremely active in lactone formation. 相似文献
12.
13.
Stahl SS 《Angewandte Chemie (International ed. in English)》2004,43(26):3400-3420
Selective aerobic oxidation of organic molecules is a fundamental and practical challenge in modern chemistry. Effective solutions to this problem must overcome the intrinsic reactivity and selectivity challenges posed by the chemistry of molecular oxygen, and they must find application in diverse classes of oxidation reactions. Palladium oxidase catalysis combines the versatility of Pd(II)-mediated oxidation of organic substrates with dioxygen-coupled oxidation of the reduced palladium catalyst to enable a broad range of selective aerobic oxidation reactions. Recent developments revealed that cocatalysts (e.g. Cu(II), polyoxometalates, and benzoquinone) are not essential for efficient oxidation of Pd(0) by molecular oxygen. Oxidatively stable ligands play an important role in these reactions by minimizing catalyst decomposition, promoting the direct reaction between palladium and dioxygen, modulating organic substrate reactivity and permitting asymmetric catalysis. 相似文献
14.
15.
16.
Defieber C Grützmacher H Carreira EM 《Angewandte Chemie (International ed. in English)》2008,47(24):4482-4502
Metal-catalyzed asymmetric processes offer one of the most straightforward ways to introduce stereogenic centers. Hence, the development of novel chiral ligands that can effectively induce asymmetry in reactions is crucial in modern organic synthesis. While many established chiral ligands bind to a metal through heteroatoms, structures that coordinate to metals through carbon atoms have received little attention so far. Here, we highlight the increasing number of such chiral chelating olefin ligands as well as their application in a variety of metal-catalyzed transformations. 相似文献
17.
介绍了双中心协同催化作用的概念以及A型和B型两类催化剂。综述了A型催化 剂在不对称硝基-类羟醛反应、迈克尔加成反应、亚胺和醛的氢膦酰化反应、曼尼 希反应、不对称醛酮羟醛反应以及环氧开环反应中的应用;同时简要介绍了B型催 化剂在不对称合成中的应用。 相似文献
18.
Directing groups have been widely used in recent years to achieve control over all aspects of reaction selectivity in a wide range of transformations involving transition-metal catalysis and organometallic reagents. In cases when the existing functional group within a substrate is unsuited to achieve efficient intramolecular delivery of a reagent or catalyst, the specific introduction of an appropriately designed removable reagent-directing group can be a solution to this problem. In this Review we give an overview of the state of the art in this area, including the stoichiometric and catalytic use of directing groups. 相似文献
19.
20.
Dr. Tomasz Ratajczyk Dr. Torsten Gutmann Dr. Piotr Bernatowicz Prof. Gerd Buntkowsky Dr. Jaroslaw Frydel Bartlomiej Fedorczyk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(36):12616-12619
Signal amplification by reversible exchange (SABRE) can enhance nuclear magnetic resonance signals by several orders of magnitude. However, until now this was limited to a small number of model target molecules. Here, a new convenient method for SABRE activation applicable to a variety of synthetic model oligopeptides is demonstrated. For the first time, a highly SABRE‐active pyridine‐based biocompatible molecular framework is incorporated into synthetic oligopeptides. The SABRE activity is preserved, demonstrating the importance of such earmarking. Finally, a crucial exchange process responsible for SABRE activity is identified and discussed. 相似文献