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Science China Chemistry 2008年第11期51卷 1074-1086页

作者： TAN YueMing XIE QingJi HUANG JinHua CHEN DaiWu CHEN Xin TU XinMan LI YunLong GE Bin YAO ShouZhuo Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Ministry of Education of China) College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China

A two-channel electrochemical quartz crystal microbalance (EQCM) was used to investigate the cyclic voltammetric behavior of two Prussian blue (PB) film-modified Au electrodes in a two-electrode con-figuration in aqueous solution. The redox peaks observed in the two-electrode cyclic voltammogram (CV) are assigned to the intrinsic redox transitions among the Everitt's salt, PB, and Prussian yellow for the film itself, the redox process of the Au substrate and the redox process of small-quantity ferri-/ferrocyanide impurities entrapped in the PB film, as also supported by ultraviolet-visible (UV-Vis) spectroelectrochemical data. The profile of the two-electrode solid-state CV for the PB powder sand-wiched between two gold-coated indium-tin oxide (ITO) electrodes is similar to that for two PB-modified Au electrodes in aqueous solution, implying similar origins for the corresponding redox peaks. The two-channel EQCM method is expected to become a highly effective technique for the studies of the two-electrode electrochemical behaviors of many other species/materials.

关键词： Prussian blue (PB) two-electrode liquid-/solid-state cyclic voltammetric behavior two-channel electrochemical quartz crystal microbalance UV-Vis spectroelectrochemistry

Study of The voltammetric Behavior of Heme and Its Direct Analysis Application

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湖北文理学院学报 1998年第2期31卷 41-46页

作者： Liu Huihong Cheng Xiantang Li jun 襄阳师范高等专科学校物理系 441053

The electroanalytic method of ferriheme was investigated bylinear sweep voltammetry in medium of 0.05M Tris+0.05MNH3-NH4Cl buffer at hang mercury drop electrodes （HMDE）. Hemeexhibits two pair reversible redox peaks and one irreversible peak. Thecathodic peak potentials are -0.236V, -0.422V and -1.408V respectively. The firstand the third peaks can be used for directly quantitative determination of hemeconcentration. The peak currents are good linear relationship hemeconcentration in ranges of 3×10-6～ 6×10-5mol/L and 3×10-7～ 1.5×10-5mol/L respectively. A preliminary discussion on properties of the hemevoltammetric behavior has been suggested.

关键词： Heme voltammetric Behavior Quantitative Analysis

Diagnosis of Sugarcane White Leaf Disease Using the Highly Sensitive DNA Based voltammetric Electrochemical Determination

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American Journal of Plant Sciences 2014年第15期5卷 2256-2268页

作者： Porntip Wongkaew Suta Poosittisak Department of Chemistry Faculty of Science Khon Kaen University Khon Kaen Thailand Plant Pathology Division Faculty of Agriculture Khon Kaen University Khon Kaen Thailand

A simple and highly sensitive analysis by electrochemical voltammetry has been developed for diagnosis of the most destructive crop disease in Thailand known as sugarcane white leaf (SCWL). Determination of the corresponding DNA interaction has been obtained from the voltammetric signals of electroactive redox methylene blue (MB) by means of cyclic and differential pulse voltammetry. In this study, a chitosan-modified glassy carbon electrode (GCE) was created by self-assembly to produce electrostatic platform for effective immobilization of the DNA. Fabrication of SCWL-DNA hybridization detection system was performed by immobilizing the ssDNA probe as a specific sensor onto chitosan-modified GCE. Hybridization of complementary DNA from the real samples could then be detected by its respective MB signal. This fabricated DNA probe sensor was shown to be capable for discriminative identification among the DNAs from SCWL plants, mosaic virus infected sugarcane and healthy sugarcane plants. Relationship between the specific hybridization signal and DNA target concentration was also observed under optimal condition. The detection limit of 4.709 ng/μl with the regression coefficient (R2) of 0.998 and overall RSD of 2.44% were obtained by response curve fit analysis. The actual SCWL-ssDNA immobilization and hybridizing event were subsequently confirmed by an observation under atomic force microscope. Thus these experiments demonstrate the first successful and effective DNA based voltammetric electrochemical determination for a verification of the specific pathogenic infection within plants from the real epidemic field.

关键词： Sugarcane White Leaf Disease Chitosan-Modified Glassy Carbon Electrode DNA Hybridization Sensor Methylene Blue voltammetric Signal Atomic Force Microscope

维生素A的电化学测定法——Ⅰ.制剂中维生素A的伏安测定(voltammetric)法

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国际药学研究杂志 1975年第2期31卷 128-129页

作者：姜心如

本文介绍了在碳糊电极上利用伏安氧化作用来测定药物制剂中维生素 A 的含量。由于不需要层析分离过程,因而大大节省时间,又可消除误差来源。大量维生素 E 的存在并不干扰测定。消除干扰的方法是将样品进行乙酰化,维生素 A

关键词：维生素乙醚提取 voltammetric 化学活性碳糊电极

Resolution method for overlapping peaks based on the fractional-order differential

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Science China Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 College of Information & Control, Nanjing University of Information Science & Technology, Nanjing 210044, China 2 College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China College of Information & Control Nanjing University of Information Science & Technology Nanjing China College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

Investigation on property and mechanism of redox wave of methylhesperidine at Hg electrode

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Science China Chemistry 2005年第Z1期48卷 20-24页

作者： ZHENG Jianbin MENG Zuchao ZHANG Hongfang Institute of Analytical Science/Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry Northwest University Xi'an 710069 China Institute of Analytical Science/Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry Northwest University Xi'an 710069 China Institute of Analytical Science/Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry Northwest University Xi'an 710069 China

The voltammetric behaviors of methylhesperidine (MH) were studied by means of linear sweep voltammetry, cyclic voltammetry and normal pulse voltammetry. In the Brit ton-Robinson buffer solutions with pH values from 2.05 to 6.37, MH could yield three reduction waves PC1, PC2 and PC3. PC1 wave is an adsorptive pre-wave. PC2 wave is an irreversible reduc tion of pre-protonated MH involving one electron and one proton. PC3 wave is an irreversible wave of reduction species radical of MH involving one electron.

关键词： voltammetric behavior, polarography, mechanism, reduction, methylhesperidine.

Rapid Detection of Escherichia coli by Electrochemical Assay of β-D-Galactosidase with p-Aminophenyl-β-D- Galactopyranoside as Substrate

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Tsinghua Science and Technology 2002年第6期7卷 624-628页

作者：黄昊肖炘高宏孙素琴冯军罗国安 Department of Chemistry Tsinghua University Beijing 100084 China

An electrochemical assay was developed for β-D-galactosidase in coliform bacteria Escherichia coli (E. coli) using p-aminophenyl-β-D-galactopyranoside (PAPG) as substrate. The hydrolysis of PAPG by pure β-D-galactosidase was investigated based on the cyclic voltammetric (CV) behavior of p-aminophenyl (PAP). The results obtained using the pure enzyme showed that the addition of magnesium ion facilitated the enzyme-catalytic reaction. K m at the optimal magnesium ion concentration (5 mmol/L) was 0.90 mmol/L. The substrate was also used for coliformbacteria, where β-D-galactosidase in the bacteria cells was strongly induced by isopropyl-β-D-thiogalactopyranoside (IPTG). When the E. coli cell density exceeded 1.1×10 3 mL -1, the CV response was linearly related to the number of E. coli, the detection time was about one hour. This method can be developed into a portable biosensor for rapid assay of coliform bacteria.

关键词： p-aminophenyl-β-D-galactopyranoside rapid assay E. coli voltammetric galactosidase

环境水样中铬(Ⅵ)和总铬的伏安法测定的研究

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福州大学学报(自然科学版) 1985年第3期 172-179页

作者：王世信王银兰林树平福州大学化学系

本文应用以难溶汞盐形式富集铬（Ⅵ）、阴极溶出伏安法测定环境水中的铬（Ⅵ）和铬（Ⅲ）并研究了以难溶汞盐形式富集铬（Ⅵ）的电积和阴极溶出的特性．方法的精密度和回收率，共存元素的干扰及其消除方法。在０．２０Ｎ的硝酸钾（ｐ... 详细信息

本文应用以难溶汞盐形式富集铬（Ⅵ）、阴极溶出伏安法测定环境水中的铬（Ⅵ）和铬（Ⅲ）并研究了以难溶汞盐形式富集铬（Ⅵ）的电积和阴极溶出的特性．方法的精密度和回收率，共存元素的干扰及其消除方法。在０．２０Ｎ的硝酸钾（ｐＨ：２～３）的溶液中，以汞膜电极为工作电极，测定了九种环境水样中铬（Ⅵ）和铬（Ⅲ）的含量，回收误差均在１０％以下。部分水样与用分光光度法进行水质普查测定总铬的结果相比较基本一致．

关键词： voltammetric DETERMINATION OF CHROMIUM (Ⅵ) CATHODIC-STRIPPING VOLTAMMETRY