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Application of Mn(Ⅱ) as a mimetic enzyme of Horseradish Peroxidase

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Chinese Chemical Letters 2005年第1期16卷 93-96页

作者： AiXiaHAN LiHongNIU RuiCHANG FuShiZHANG KeyLabofOrganicOptoelecronics＆MolecularEngineeringofMinistryofEducation DepartmentofChemistryTsinghuaUniversityBeijing100084／／CheimcalEngineeringCollegeofQinghaiUniversityXining810016 KeyLabofOrganicOptoelecronics＆MolecularEngineeringofMinistryofEducation DepartmentofChemistryTsinghuaUniversityBeiiing100084 DepartmentofBiologicalScienceandBiotechnology TsinghuaUniversityBeijing100084

In this study, Mn(Ⅱ) as a mimetic enzyme of horseradish peroxidase (HRP) was applied to the determination of hydrogen peroxide (H2O2). The method introduced in this paper is based on Mn(Ⅱ)’s catalytic effect on the oxidation of 4-aminoantipyrine(4-AAP) with modified Trinder’s reagent N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3, 5-dimethoxyaniline(DAOS) by H2O2. By coupling this mimetic catalytic reaction with the catalytic reaction of glucose oxidase (GOD), glucose can be detected. Under optimum conditions, the calibration graphs for the determination of H2O2 and glucose are in the range of 1.0×10-3?1.0×10-1 mol/L and 1.0×10-3?14×10-3 mol/L respectively. The detection limit is 5.9×10-4 mol/L for H2O2 and is 9.2×10-4 mol/L for glucose. The feasibility of Mn ( II ) as a HRP mimetic enzyme in practical clinical analysis has been proven in the determination of glucose in human serum. So far, Mn ( II ) is the simplest and the most inexpensive mimetic enzyme.

关键词： Mn ( II ) mimetic enzyme spectrophotometry hydrogen peroxide glucose.

Myoglobin as mimetic enzyme and Its Analytical Application in Determination of H_2O_2

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 677-681页

作者： ZHENG Qi CAO Qihua LIU Zhihong CAI Ruxiu College of Chemistry and Environmental Engineering Jianghan University Wuhan 430052 Hubei China College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 Hubei China

The characteristic of Myoglobin as mimetic enzyme was studied and applied in the determination of HeO2 with o-phenylenediamine as substrate. The absorbanee obtained at 40 ℃ was found to be proportional to the concentration of H2O2 in the range of 2.0×10^-5- 2.0×10^-7 mol/L, with a correlation coefficient of 0.999 1. The proposed meth od is simple and highly sensitive to a detection limit of 2.7 × 10^-8 mol/L. The relative standard deviations were within 5% for the determination of different concentrations of H2O2. Satisfied results were obtained in the determination of H2O2 in rainwater by this method, and the recoveries were at the range of 97.2%-105.4%.

关键词： myoglobin hydrogen peroxide mimetic enzyme stopped-flow spectrophotometry

Tunable catalytic activity of FeWO_(4) nanomaterials for sensitive assays of pyrophosphate ion and alkaline phosphatase activity

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Science China Chemistry 2023年第6期66卷 1860-1868页

作者： Xianqing Tang Jinghuang Chen Mengqian Zhang Jian Sun Xiurong Yang State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry University of Science and Technology of ChinaHefei 230026China

Alkaline phosphatase(ALP)activity and pyrophosphate ion(PPi)levels are remarkable for the human body functions such as signal transduction pathways and metabolism.Current quantitative methods mainly focus on developing complicated organic substrates or employing unstable metal ions as signal-regulated medium.Herein,we have developed a facile hydrothermal method for preparing Fe WO_(4)nanomaterials with intrinsic peroxidase-like activity and further confirmed that such a catalytic activity could be significantly enhanced by adjusting the size and oxygen vacancy content.More encouragingly,PPi can easily inhibit the catalytic activity of Fe WO_(4),whereas orthophosphate ions(Pi)cannot.Therefore,we constructed an Fe WO_(4)-based colorimetric assay for sensing PPi by means of the classical 3,3′,5,5′-tetramethylbenzidine-peroxidase chromogenic reaction.A facile and reliable ALP activity assay was also designed and developed because of the logical regulation of the peroxidase-like activity of Fe WO_(4)through the ALP-catalyzed hydrolysis of PPi into Pi.Based on the clear mechanism and mimetic-enzyme Fe WO_(4)-catalyzed amplification,the sensing system exhibited excellent performance and was able to evaluate ALP activity in real serum samples and screen for potential ALP inhibitors.The proposed mimetic enzyme-involved colorimetric assay provides an alternative pathway,and Fe WO_(4)nanomaterials with excellent performance have great potential for further biosensing and biomedical applications.

关键词： FewO4 nanomaterials mimetic enzyme oxygen vacancy colorimetry pyrophosphate ion alkaline phosphatase

Effect of Solvents on Oxidation of 1,1′-Bi-2-naphthol

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Chemical Research in Chinese Universities 2005年第1期21卷 88-91页

作者： SONGJi-guo SHENPei-kang StateKeyLaboratoryofOptoelectronicMaterialsandTechnologies SchoolofPhysicsandEngineeringSunYat-SenUniversityGuangzhou510275P.R.China

A novel biomimetic catalyst of complex Cu(p-OTs) 2/ethanolamine(1∶1) was used to oxidize 1,1′-bi-2-naphthol into xanthene derivatives with a relative high yield in a mixed solvents of dimethyl sulfoxide(DMSO) and CH 3OH. The studies on the effect of some solvents on the yield of xanthene derivatives indicates that the yield reduces dramatically with the increase of the content of H 2O in the mixed solvents of H 2O and DMSO. No product can be obtained when the content of H 2O is up to 70%. The cyclic voltammetric study demonstrated that the copper ion in complex Cu(p-OTs) 2/ethanolamine(1∶1) is reduced via a two-step one-electron reduction process from Cu(Ⅱ) to Cu in the mixture of DMSO and H 2O. Water as a poor solvent in respect to the reactants probably hampered the coordination of 1,1′-bi-2-naphthol to copper/amine complex and led to the insufficient catalytic efficiency of complex Cu(p-OTs) 2/ethanolamine(1∶1).

关键词： Copper p-toluenesulfonate mimetic enzyme Xanthene Electrochemistry

Study on the Intermediate in the o-Phenylenediamine Oxidative Reaction Using Hemoglobin as A mimetic Peroxidase in Aqueous-Organic Two Phase

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 117-121页

作者： Li Hai-cheng Li De-jia Huang Bo Jin De-long Zou Guo-lin College of Life Sciences Wuhan University Wuhan 430072 Hubei China

Hemoglobin was used as a mimetic enzyme for peroxidase to catalyze the oxidative reaction of o-phenylenediamine with H2O2 which functioned as an oxidant. The relationship between physicochemical properties of the intermediate and enzymatic activity of hemoglobin was studied. Since the solubility of the intermediate in the reaction is higher in butanol phase than in water phase, the intermediate itself diffused from the aqueous phase to the butanol phase. The experimental results showed that the rate of product and the stability of intermediate were associated with the temperature and the pH value of the buffer. The formation rate of intermediate and half-life period reveal the maximal in pH7, nevertheless, the whole rate of the catalytic reaction is the greatest in pH5, which the ratio of the initial rate in final product formation compared to that intermediate formation is the greatest.

关键词： hemoglobin mimetic enzyme intermediate two phase reaction mechanism

Study on mimetic Peroxidase and Molecular Recognition of Phenols With Inclusion Complex of Ironporphyrin Immobilized by β-CD Polymer

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Wuhan University Journal of Natural Sciences 2000年第1期5卷 101-105页

作者： MAO Lu-yuan YUAN Hong CAI Ru-xiu SHEN Han-xi ZHU Min LIU Liu-zhan ( College of Chemistry and Environmental Scicence, Wuhan University, Wuhan 430072, China College of Chemistry, Nankai University, Tianjin 300071, China) College of Chemistry and Environmental Scicence Wuhan University Wuhan 430072 China College of Chemistry Nankai University Tianjin 300071 China

β-Cyclodextrin (β-CD) and its cross-linked polymer (β-CDP) were known as the mimetic models. Metalloporphyrin had been widely used in the enzymatic method of analysis and molecular recognition. In present work, it was investigation that supramolecular recognition for halogenated phenols, three crosols, three nitrophenols and three aminophenols, served respectively as the substrate of the mimetic receptor, iron-5, 10, 15, 20-tetrakis (sulforphenyl)-21H, 23H-porphine (FeTPPS) or FeTPPS-β-CDP. Supramolecular complex, FeTPPS-β-CDP with function of mult i-recognition and induced-fit, was a advanced kind of mimetic peroxidase; Methyl phenol or polyphenol was the substitute of chlorophenic acid, while aminophenols and other phenols were suggested not to be utilized to enzymatic assay of H2O2. Being a mimetic enzyme mimicking the space structure of overall proteinase, beaimed by immobilized mimetic enzyme with a large number of β-CD interior cavities, chlorophenol was identified optimal substrate in the system tested.

关键词： β CD polymer metalloporphyrin mimetic enzyme molecular recognition CLC number O 567. 3 O 477

Fluorescence Spectra and Enzymatic Property of Hemoglobin as mimetic Peroxidase

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Wuhan University Journal of Natural Sciences 2003年第3A期8卷 875-879页

作者： Li De\|jia, Li Hai\|cheng, Zou Guo\|lin  College of Life Sciences, Wuhan University, Wuhan 430072, Hubei, China College of Life Sciences Wuhan University Wuhan 430072 Hubei China

Intrinsic fluorescence emission maxima of hemoglobin(Hb) was investigated in relation to peroxidase property of Hb. The peroxidase activity of Hb was based on its ca\| talytic activity for oxidation of o \|phenylenediamine by hydrogen peroxide. Hb was treated in the condition (temperature, ethanol and salt) that tetramer\|dimer equilibrium of Hb is shifted to the dimer state and its fluorescence spectrum was measured . When Hb treated in temperature (60\|70 ℃), ethanol concentration (60%\|70%) and NaCl concentration (2.5\|3.0 mol/L), the fluorescence emission maxima of Hb shifted towards red wavelength and its activity decreased quickly. Experimental results revealed that the activity and stability of Hb as mimetic peroxidase was closely relative to the hydrophobic environment of active center of Hb, and when Hb (Fe Ⅱ ) converted into met Hb (Fe Ⅲ ), its activity was 1.6 times as much as that of Hb.

关键词： hemoglobin intrinsic fluorescence mimetic enzyme structure\|function