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Chinese Journal of Chemistry 2003年第6期21卷 687-692,594页

作者：吕鉴泉何锡文曾宪顺张海丽张正之 State Key Laboratory of Elemento Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China Department of Chemistry Hubei Normal University Huangshi Hubei 435002 China State Key Laboratory of Elemento Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China Department of Chemistry Hubei Normal University Huangshi Hubei 435002 China

A new glassy carbon electrode modified with novel caHx[4]arene derivative was prepared and then applied to the selective recognition of lead ion in aqueous media by cyclic and square wave voltammtry. A new anodic stripping peak at - 0.92 V (vs. Ag/Ag+) in square wave voltammogram can be obtained by scanning the potential from - 1.5 to - 0.6 V, of which the peak current is proportional to the concentration of Pb2+. The modified electrode in 0.1 moVL HNO3 solution showed a linear voltammetric response in the range of 2.0 x 10(-8)-1.0 x 10(-6) mol/L and a detection limit of 6.1 x 10(-9) mol/L. In the modified glassy carbon electrode no significant interference occurred from alkali, alkaline and transition metal ions except Hg2+, Ag+ and Cu2+ ions, which can be eliminated by the addition of KSCN. The proposed method was successfully applied to determine lead in aqueous samples.

关键词： calixarene derivative glassy carbon electrode square wave voltarnmetry lead ion

Amperometric Biosensor for Hydrogen Peroxide Based on electrodeposited Sub-micrometer Gold Modified glassy carbon electrode

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Chinese Journal of Chemistry 2004年第4期22卷 360-364页

作者：王树青陈峻林祥钦 Department of Chemistry University of Science and Technology of China

A new type of hydrogen peroxide amperometric biosensor was fabricated based on electrochemically deposited sub-micrometer Au particles (sm-Au) on a glassy carbon electrode (GCE). Electrochemical deposition condition was optimized for obtaining uniformly distributed sub-micrometer sized Au array on the electrode surface. The hy-drogen peroxide sensor was fabricated by adsorbing phenothiazine methylene blue (MB) molecules on the surface of sm-Au and covering a cross-linked horseradish peroxidase (HRP) layer, labeled as HRP/MB/sm-Au/GCE. The characteristics of this biosensor were evaluated with respect to applied potential and pH. The amperometric re-sponse of the sensor was linear to the H2O2 concentration over a wide range of 9.9×10-61.11×10-2 mol/L. A detection limit (s/n=3) of 3.0×10-6 mol/L H2O2 was estimated for a sampled chronoamperometric detection at 1.5 min after potential step of 200 to -400 mV vs. SCE. The immobilized MB molecules shuttled electrons at a=0.77 and an apparent electron transfer rate constant of 0'sk=0.053 s-1. Interference of ascorbic acid, dopamine and uric acid was investigated. This sensor has very good stability and reproducibility for long-term use.

关键词： hydrogen peroxide amperometric biosensor sub-micrometer gold glassy carbon electrode me-thylene blue horseradish peroxidase

Direct Electrochemistry and Electrocatalysis of Hemoglobin at PAMAM Dendrimer-MWNTs-Au Nanoparticles Composite Film Modified glassy carbon electrode

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Chemical Research in Chinese Universities 2010年第5期26卷 723-728页

作者： LIU Xing-mei ZHANG Xue-yu ZHAO Yi-li LIU Wei-lu WANG Bao-jun ZHANG Yi-hua ZHANG Zhi-quan College of Chemistry Alan G. MacDiarmid lnstitute Jilin University Changchun 130012 R R. China

The direct electron transfer of hemoglobin at the PAMAM-MWNTs-AuNPs composite film modified glassy carbon electrode was studied. In a phosphate buffer solution（PBS, pH=7.0）, the formal potential（E^0） of Hb was -0.105 V versus SCE, the electron transfer rate constant was 4.66 s-1. E^0＇ of Hb at the modified electrode was linearly varied in a pH range of 5.0-8.0 with a slope of-49.2 mV/pH. The Hb/PAMAM-MWNTs-AuNPs/GCE gave an excellent electrocatalytic response to the reduction of hydrogen peroxide. The catalytic current increased linearly with H2O2 concentration in a range of 1.0× 10^-6 to 2.2× 10^-3 mol/L. The detection limit was 2.0× 10^-7 mol/L at a signal to noise ratio of 3. The Michaelis-Menten constant（Km^app） was 2.95 mmol/L.

关键词： Direct electrochemistry Electrocatalysis Hemoglobin PAMAM dendrimer-MWNTs-Au nanoparticles composite glassy carbon electrode

Voltammetric behavior of sedative drug midazolam at glassy carbon electrode in solubilized systems

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Journal of Pharmaceutical Analysis 2012年第2期2卷 123-129页

作者： Rajeev Jain Rajeev Kumar Yadav School of Studies in Chemistry Jiwaji University

Redox behavior of midazolam was studied at a glassy carbon electrode in various buffer systems,supporting electrolytes and pH using differential paise,square-wave and cyclic voltammetry.Based on its reduction behavior,a direct differential pulse voltammetric method has been developed and validated for the determination of midazolam in parenteral dosage.Three welldefined peaks were observed in 0.1％ SLS,Britton-Robinson (BR) buffer of pH 2.5.The effect of surfaetants like sodium lauryl sulfate (SLS),cetyl trimethyl ammonium bromide (CTAB) and Tween 20 was studied.Among these surfactants SLS showed significant enhancement in reduction peak.The cathodic peak currents were directly proportional to the concentration of midazolam with correlation coetfficient of 0.99.

关键词： Midazolam Voltammetry Surfactant glassy carbon electrode Parenteral dosage form

Cyclic Voltammetry Determination of Epinephrine with a Nano-gold Modified glassy carbon electrode in the Presence of High Concentration Ascorbic Acid

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Chinese Chemical Letters 2002年第2期13卷 153-156页

作者： HongZHANG XueQinGUI 等 SchoolofChemistryandChemicalEngineering AnhuiUniversityHefei230039 TheCenterofModernExperimentandTechnology AnhuiUniversityHefei230039

Nano-gold (NG) modified glassy carbon electrodes (GCEs) were used for determination of epinephrine (EP) in the presence of high concentration ascorbic acid (AA) by cyclic voltammetry (CV). This modified electrode can not only catalytically oxidize EP and AA, but also separate the catalytic peak potentials of EP and AA by about 183.5 mV. In pH = 7.0 ogisogate byffer solution, the linear range of epinephrine was 5 106 ~ 1 ?10-4 mol/L.

关键词： Nano-gold glassy carbon electrode epinephrine ascorbic acid cyclic voltammetry.

Bilirubin sensor based on CuO-CdO composites deposited in a nafion/glassy carbon electrode matrixes

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Progress in Natural Science:Materials International 2017年第5期27卷 566-573页

作者： Mohammed M.Rahman Mohammad Musarraf Hussain Abdullah M.Asiri Chemistry Department King Abdulaziz UniversityFaculty of Science Center of Excellence for Advanced Material Research (CEAMR) King Abdulaziz University

Copper oxide-cadmium oxide nanocomposites(CuO-CdO NCs) were synthesized by solvothermal technique in a basic medium. CuO-CdO NCs were characterized using conventional techniques, such as Fourier Transform Infrared Spectroscopy(FTIR), UV–Visible Spectroscopy(UV/Vis), Field-Emission Scanning Electron Microscopy(FESEM), X-ray electron dispersive spectroscopy(XEDS), X-ray photoelectron spectroscopy(XPS), and powder X-ray diffraction(XRD). A selective and enzyme-less Bilirubin(BLR) sensor was developed with a thin-layer of NCs onto a glassy carbon electrode(GCE, surface area = 0.0316 cm~2) using 5% nafion binders at room conditions. Improved electrochemical performances of higher sensitivity, lower detection limit,linear dynamic range(LDR), and long-term stability of preferred BLR were achieved by a reliable currentvoltage(I-V) approach. The calibration curve was found linear(R~2= 0.9347) in a wide range of BLR concentration(10.0 pM ~ 10.0 mM). Based on the signal to noise ratio value of 3, the sensitivity and limit of detection(LOD) of the sensor were calculated as 95.0 pA μM-1cm-2and 1.0 ± 0.1 pM respectively.Solvothermally synthesized CuO-CdO NCs/GCE is an excellent advancement of developing a selective and sensitive BLR sensor by electrochemical approach and practically implemented in real sample applications.

关键词： CuO-CdO nanocomposites Bilirubin biosensor glassy carbon electrode Sensitivity Real sample analysis Health care field

Voltammetric Response of Epinephrine at carbon Nanotube Modified glassy carbon electrode and Activated glassy carbon electrode

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 913-918页

作者： WANG Juan TANG Ping ZHAO Fa-qiong ZENG Bai-zhao College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 Hubei China Department of Environmental Engineer Jianghan University Wuhan 430000 Hubei China

The electrochemical behavior of epinephrine at activated glassy carbon electrode and carbon nanotube-coated glassy carbon electrode was studied. Epinephrine could exhibit an anodic peak at about 0.2 V （vs. SCE） at bare glassy carbon electrode, but it was very small. However, when the electrode was activated at certain potential （i.e. 1.9 V） or modified with carbon nanotube, the peak became more sensitive, resulting from the increase in electrode area in addition to the electrostatic attraction. Under the selected conditions, the anodic peak current was linear to epinephrine concentration in the range of 3.3×10^-7 - 1.1×10^-5 mol/L at activated glassy carbon electrode and in the range of 1.0×10^-5 - 5.0×10^-5 mol/L at carbon nanotube-coated electrode. The correlation coefficients were 0.998 and 0.997, respectively. The determination limit was 1.0×10^-7 mol/L. The two electrodes have been successfully applied for the determination of epinephrine in adrenaline hydrochloride injection with recovery of 95%-104%.

关键词： epinephrine carbon nanotube glassy carbon electrode modified electrode

Voltammetric quantitation of nitazoxanide by glassy carbon electrode

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Journal of Pharmaceutical Analysis 2013年第6期3卷 452-455页

作者： Rajeev Jain Rajeev Kumar Yadav Jahangir Ahmad Rather School of Studies in Chemistry Jiwaji University

The present study reports voltammetric reduction of nitazoxanide in Britton-Robinson （B-R） buffer by cyclic and square-wave voltammetry at glassy carbon electrode. A versatile fully validated voltammetric method for quantitative determination of nitazoxanide in pharmaceutical formulation has been proposed. A squrewave peak current was linear over the nitazoxanide concentration in the range of 20-140 ~tg/mL. The limit of detection （LOD） and limit of quantification （LOQ） was calculated to be 5.23 la~/mL and 17.45 la~/mL, respectively.

关键词： Nitazoxanide Squarewave voltammetry glassy carbon electrode Pharmaceuticalformulation

Electrochemical behavior of paclitaxel and its determination at glassy carbon electrode

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Asian Journal of Pharmaceutical Sciences 2014年第1期9卷 42-49页

作者： Jayant I.Gowda Sharanappa T.Nandibewoor P.G.Department of Studies in Chemistry Karnatak UniversityDharwad 580003Indi

The electrochemical behavior of paclitaxel drug was studied at a glassy carbon electrode in phosphate buffer solutions using cyclic and differential-pulse voltammetric techniques.The oxidation process was shown to be irreversible over the pH range(3.0e10.4)and was diffusion controlled.Effects of anodic peak potential(E_(p)),anodic peak current(Ipa),scan rate,pH,heterogeneous rate constant(k^(0)),etc have been discussed.A possible electrooxidation mechanism was proposed.An analytical method was developed for the determination of paclitaxel in phosphate buffer solution at pH¼7.0 as a supporting electrolyte.The anodic peak current varied linearly with paclitaxel concentration in the range 1.0×10^-(6)M to 1.0×10^-(5)M with a limit of detection(LOD)of 1.23×10^(-8)M and limit of quantification(LOQ)of 4.10×10^(-8)M.The proposed method was successfully applied to the determination of paclitaxel in pure and real samples.

关键词： Paclitaxel glassy carbon electrode Voltammetry Injection analysis Urine

Voltammetric Detection of Nanomolar Levels of Hypoxanthine in the Presence of Copper(Ⅱ) at glassy carbon electrode

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Wuhan University Journal of Natural Sciences 1999年第1期4卷 101-104页

作者： 1) Hu Shengshui, 2) Cui Dafu, 3) Marco Mascini 1) College of Chemistry, Wuhan University, Wuhan 430072, China 2) State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of S

Nanomolar levels of the hypoxanthine in NaOH electrolyte cantaining copper(Ⅱ) can be determined by anodic stripping voltammetry at a glassy carbon electrode. In the present article hypoxanthine Cu + is shown to be adsorbed on the electrode surface in the presence of an excess of copper(Ⅱ). After accumulation period, hypoxanthine Cu + was stripped from the electrode surface and the anodic current coming near to the oxidation of Cu(Ⅰ) to Cu(Ⅱ) was measured. A linear calibration curve in the range of 5 nmol/L 1.5 mmol/L hypoxanthine, with a detection limit of 0.5 nmol/L hypoxanthine were obtained.

关键词： hypoxanthine copper glassy carbon electrode stripping voltammetry