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1.
一种新的乙酰胆碱酶电极的研究 总被引:5,自引:0,他引:5
本文制备了一种以溶剂聚合膜PH电极作原电极,经高碘酸钠活化的醋酸纤维膜固定乙酰胆碱酯酶的乙酰胆碱生物电极。研究了酶固定化条件的影响,测得静态和动力学条件下的线性中响应范围分别为240-1300μg/mL和300-1700μg/mL将电极用于实际样品的回收率试验中,获得了满意的结果。 相似文献
2.
《Electroanalysis》2006,18(5):465-470
Nickel and platinum find extensive use in preparation of biosensors. In the present work, Ni/Pt alloy was plated on graphite to make acetylcholine sensor. The microstructure, surface composition and electrochemical performance of the electrode was analyzed by different techniques. The sensing performance was evaluated by cyclic voltammetry. The prepared alloy plate exhibited very good linear relationship between acetyl choline concentration and response current. The sensitivity and reproducibility of the prepared electrode were found better than other nickel electrodes reported. 相似文献
3.
《Electroanalysis》2003,15(14):1185-1191
We tested a new design of an enzyme biosensor based on acetylcholinesterase (AChE) and choline oxidase (ChO) immobilized on the supported monomolecular layer composed of poly(amidoamine) (PAMAM) dendrimers of the fourth generation (G4) mixed with 1‐hexadecanethiol (HDT). The resulting enzymatic activity, measured amperometrically, was substantially depressed in the presence of the organophosphate pesticide dimethyl‐2,2‐dichlorovinylphosphate (DDVP, Dichlorvos), carbamate pesticides carbofuran and carbamate drug eserine. The detection limits (1.3×10?3 ppb for DDVP, 0.01 ppb for carbofuran and 0.03 for eserine) were considerably lower than so far reported for AChE based amperometric and potentiometric sensors. The relative simple protocol of biosensor preparation, high sensitivity and stability is very promising for determination of environmental pollutants in field conditions. 相似文献
4.
Langlet J. Claverie P. Pullman B. Piazzola D. Daudey J. P. 《Theoretical chemistry accounts》1977,46(2):105-116
The effect of water on the conformational preferences of acetylcholine has been studied within the discrete, the continuum and the combined discrete-continuum models described in parts I and II of this series. All the models lead to the conclusion that the trans-gauche form which is, following refined quantum-mechanical computations, the intrinsically preferred one and the one observed in the crystal of acetylcholine and of a number of analogues should remain also the preferred conformation in water. This result agrees with NMR studies. The results of the empirical discrete model used here compare favorably to those obtained by an ab initio super-molecule treatment. The continuum model utilized here represents a net improvement above such models utilized in other works. 相似文献
5.
Amperometric enzyme biosensors for the determination of acetylcholine (ACh) and choline (Ch) have been described. For the fabrication of the biosensors, N-acetylaniline (nAN) was first electropolymerized on a Pt electrode surface to be served as a permselective layer to reject interferences. Bovine serum albumin (BSA) and choline oxidase (CHOD) were co-immobilized in a zinc oxide (ZnO) sol–gel membrane on the above modified Pt electrode for a Ch sensor, or CHOD, acetylcholinesterase (AChE) and BSA immobilized together for an ACh/Ch sensor. The poly (N-acetylaniline) (pnAN) film was the first time used for an ACh/Ch sensor and found to have excellent anti-interference ability, and the BSA in the sol–gel can improve the stability and activity of the enzymes. Amperometric detection of ACh and Ch were realized at an applied potential of +0.6 V versus SCE. The resulting sensors were characterized by fast response, expanded linear range and low interference from endogenous electroactive species. Temperature and pH dependence and stability of the sensor were investigated. The optimal ACh/Ch sensor gave a linear response range of 1.0 × 10−6 to 1.5 × 10−3 M to ACh with a detection limit (S/N = 3) of 6.0 × 10−7 M and a linear response range up to 1.6 × 10−3 M to Ch with a detection limit of 5.0 × 10−7 M. The biosensor demonstrated a 95% response within less than 10 s. 相似文献
6.
《Analytical letters》2012,45(2):258-265
Electrogravimetric analysis was performed on the consumption of the neurotransmitter Acetylcholine (ACh) by Acetylcholinesterase (AChE) in situ and in real time. Michaelis-Menten assumption was achieved by using an enzyme micro-reactor in which the total enzyme was anchored in a quartz crystal microbalance chip (QCM-chip) with a strategically engineered self-assembled monolayer (SAM) of alkanethiols, which can prevent diffusion-controlled or spatially restricted kinetics. The real-time frequency changes indicated the rate of the products formation from enzymatic reaction. The QCM-chip was tested showing that it could demonstrate AChE inhibition by physostigmine. 相似文献
7.
An acetylcholine sensor was constructed with acetylcholinesterase which was immobilized on a hydrogen ion-selective coated-wire electrode and fundamental properties of this sensor were investigated. Acetylcholine could be determined in the range 0.1–10 rum with response times of 3–10 min. The effects of pH and concentration of buffer solution on the determination and fluctuations in the data obtained with this sensor were also investigated. Possibilities for the practical use of this acetylcholine micro-sensor are suggested. 相似文献
8.
Structural Dynamics of Amyloid β Peptide Binding to Acetylcholine Receptor and Virtual Screening for Effective Inhibitors 下载免费PDF全文
Yan-jun Hou Xuan Zheng Hong-mei Zhong Feng Chen Gui-yang Yan Kai-cong Cai 《化学物理学报(中文版)》2021,34(3):323-333
The interaction between Amyloid β (Aβ) peptide and acetylcholine receptor is the key for our understanding of how Aβ fragments block the ion channels within the synapses and thus induce Alzheimer's disease. Here, molecular docking and molecular dynamics (MD) simulations were performed for the structural dynamics of the docking complex consisting of Aβ and α7-nAChR (α7 nicotinic acetylcholine receptor), and the inter-molecular interactions between ligand and receptor were revealed. The results show that A\begin{document}$ \beta_{25-35} $\end{document} is bound to α7-nAChR through hydrogen bonds and complementary shape, and the A\begin{document}$ \beta_{25-35} $\end{document} fragments would easily assemble in the ion channel of \begin{document}$ \alpha $\end{document} 7-nAChR, then block the ion transfer process and induce neuronal apoptosis. The simulated amide-I band of A\begin{document}$ \beta_{25-35} $\end{document} in the complex is located at 1650.5 cm\begin{document}$ ^{-1} $\end{document} , indicating the backbone of A\begin{document}$ \beta_{25-35} $\end{document} tends to present random coil conformation, which is consistent with the result obtained from cluster analysis. Currently existing drugs were used as templates for virtual screening, eight new drugs were designed and semi-flexible docking was performed for their performance. The results show that, the interactions between new drugs and \begin{document}$ \alpha $\end{document} 7-nAChR are strong enough to inhibit the aggregation of A\begin{document}$ \beta_{25-35} $\end{document} fragments in the ion channel, and also be of great potential in the treatment of Alzheimer's disease. 相似文献
9.
Tsung-Ying Shen 《中国化学会会志》1995,42(4):617-621
Following the discovery of salicylates and its conversion to aspirin, natural products research has provided many promising leads for further modification as anti-inflammatory and analgesic agents. Recent studies have focused on biosynthesis inhibitors of eicosanoids and receptor antagonists of the platelet activating factor, including a new class of dual functional inhibitors derived from neolignans. The highly potent analgesic alkaloid epibatidine from the frog skin has been synthesized and recharacterized as a very strong acetylcholine nicotinic receptor agonist. Some novel epibatidine analogs have shown promise as potential CNS drugs and research probes for clarifying the anti-addictive property of the African alkaloid ibogaine. 相似文献
10.
《Arabian Journal of Chemistry》2022,15(11):104189
The quality of grains is influenced by storage pests, which are not only spoilers of stored grain, but also vectors of human and animal diseases. Chemical pesticides play an essential role in the cultivation and storage of cereals, however, due to the low degradability and residual toxicity of synthetic pesticides on the environment and non-target organisms, as well as the increasing resistance of target organisms to them, consideration should be given to the development of alternative pest control agents. Compounds isolated from natural sources have emerged as preferred targets for the development of novel insecticidal agents because of their eco-friendliness, safety, and effectiveness. In this review, we primarily focus on the natural product (NPs) control of storage pests. The effective monomer components of NPs and their anti-insect mechanisms were discussed, and natural sources of inspiration and models for insect repellents are described. This review aimed to provide guidelines for the exploitation and utilization of green and efficient natural insecticides. 相似文献