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Mathematical Modelling of the Electrode Process of Azithromycin Using Cyclic Voltammetry at Hanging Mercury Drop Electrode  [PDF]
Reyad A. Shawabkeh,Maha F. Tutunji
Sensors , 2002, DOI: 10.3390/s21100436
Abstract: A theoretical treatment is presented to predict the kinetic behaviour of azithromycin at the surface of hanging mercury drop electrode using cyclic voltammetry. A model is developed to incorporate the occurrence of adsorption of the oxidized and reduced species of azithromycin at the surface of mercury drop electrode. An analytical solution was obtained using MATHEMATICA (V-3, Wolfram Research, Inc.) to predict the cyclic voltammetric profiles by calculating the currents resulting after applying variable potentials ranging –1.9 to –1.3 V versus Ag/AgCl. Simulation runs at different initial concentrations of azithromycin and different scan rates showed good agreement with experimental findings. However, this model should be modified to describe a multilayer adsorption with irreversible electrochemical reaction.
ELECTROSYNTHESIS AND CHARACTERISATION OF A COBALT HEXACYANOFERRATE–POLY(3 METHYL-THIOPHENE) MODIFIED PLATINUM ELECTRODE USING CYCLIC VOLTAMMETRY  [PDF]
Ileana Sandu,Ioana Vlaicu,Alina Cristian,C. Mihailciuc
Analele Universitatii Bucuresti : Chimie , 2008,
Abstract: The scope of the present paper is to prepare and to study a bilayer chemically modified electrode (BCME) synthesized by successive electrodeposition of an inorganic (inner) layer of cobalt hexacyanoferrate (CoHCF) and of an organic (outer) layer of poly(3-methylthiophene) (P3MT) on a platinum electrode surface and to investigate the electrochemical behaviour of this BCME in various transfer electrolyte solutions. Both the preparation and the characterization of the BCME were studied using cyclic voltammetry (CV) technique. The role of the doping/undoping cation used in the electrolyte solution is emphasised.
ELECTROCHEMICAL PREPARATION AND CHARACTERIZATION OF POLY (3-METHYLTHIOPHENE)-COBALT HEXACYANOFERRATE–MODIFIED PLATINUM ELECTRODE USING CYCLIC VOLTAMMETRY  [PDF]
Andra Sorina Dobre,Mirela Dascalu,C. Mihailciuc
Analele Universitatii Bucuresti : Chimie , 2008,
Abstract: Using consecutive cyclic voltammetry (CV), cobalt (II) hexacyanoferrate (CoHCF) and cobalt (II) hexacyanoferrate/poly (3-methyl thiophene) (CoHCF/P3MT) films have been prepared in fresh solutions formed between CoCl2 1mM, K3[Fe(CN)6] 0.5 mM and KCl 0.5 M for the Pt/CoHCF electrode and DMSO as a solvent, TBAPF6 0.1M and 3MT 50mM for the Pt/P3MT/CoHCF electrode. Then, using different cyclic voltammetry techniques, chemically modified electrodes, Pt/CoHCF and Pt/P3MT/CoHCF, were used to study their response in a phosphate buffer system of 7.2 pH and in ascorbic acid of various concentrations.
CO adsorption on electrode of Pt nanoparticles investigated by cyclic voltammetry and in situ FTIR spectroscopy
Wei Chen,Yanxia Jiang,Shigang Sun
Chinese Science Bulletin , 2003, DOI: 10.1360/03tb9027
Abstract: Pt nanoparticles were prepared by the chemical reduction method. The average diameter of Pt nanoparticles was determined to be 2.5 nm by TEM. The electrochemical properties of Pt nanoparticles were studied by cyclic voltammetry. In comparison with massive Pt, the oxidation current peak of CO adsorbed on Pt nanoparticles is broader. Twin adsorbates of CO on Pt nanoparticles were determined by in situ FTIRS for the first time. It has revealed that the linear and twin-bonded CO can be converted into bridge-bonded CO with the variation of electrode potential. A series of special properties of Pt nanoparticles, such as enhanced IR absorption of CO adsorbates, were also observed.
PREPARATION OF MANGANESE DIOXIDE MODIFIED GLASSY CARBON ELECTRODE BY A NOVEL FILM PLATING/CYCLIC VOLTAMMETRY METHOD FOR H(2)0(2) DETECTION
WEN-ZHI,LE; YOU-QIN,LIU; GUANG-QI,HU;
Journal of the Chilean Chemical Society , 2009, DOI: 10.4067/S0717-97072009000400009
Abstract: manganese dioxide modified glassy carbon electrode (mn02/gc) was prepared by a novel film plating/cyclic voltammetry method for the determination of h202. a manganese film was first cathodically deposited on the surface of glassy carbon electrode from mncl2 solution at the potential of-1.4 v versus ag/ agcl (satd. kc1), and then a well defined manganese dioxide was deposited on the surface of glassy carbon electrode by cyclic voltammetry at potential range -0.6 ~ 0.6 v, scan rate 100 mv s-1 in 0.1 mol l71 naoh solution. the resulted modified electrode was characterized by cyclic voltammetry and scanning electron microscopy (sem), which showed excellent electrocatalytic activity for the oxidation of h202. the chronoamperometric detection of h202 was carried out at 0.6 v in phosphate buffer solution ph 7.38 containing 0.1 mol l71 kc1 and the linear relationship of response current on h202 concentration was obtained in the range from 4. ixl0~10 to lxl0~-mol l-1 with a minimum detectable concentration of 3xl0~10 mol l71 [s/n (signal noise ratio) = 3]. the response time of the electrode to achieve 95% of the steady-state current was < 2 s. no measurable reduction in analytical performance of the modified electrode was found by storing the electrode in ambient conditions for 30 days. this modified electrode has many advantages such as simple preparation procedure, remarkable catalytic activity, good reproducibility and long term stability of signal response during hydrogen peroxide oxidation. the deposition of manganese dioxide on the surface of gc appears to be a highly efficient method for the development of a new class of sensitive, stable and reproducible hydrogen peroxide electrochemical sensor.
PREPARATION OF MANGANESE DIOXIDE MODIFIED GLASSY CARBON ELECTRODE BY A NOVEL FILM PLATING/CYCLIC VOLTAMMETRY METHOD FOR H(2)0(2) DETECTION  [cached]
LE WEN-ZHI,LIU YOU-QIN,HU GUANG-QI
Journal of the Chilean Chemical Society , 2009,
Abstract: Manganese dioxide modified glassy carbon electrode (Mn0(2)/GC) was prepared by a novel film plating/cyclic voltammetry method for the determination of H(2)0(2). A manganese film was first cathodically deposited on the surface of glassy carbon electrode from MnCl2 solution at the potential of-1.4 V versus Ag/ AgCl (satd. KC1), and then a well defined manganese dioxide was deposited on the surface of glassy carbon electrode by cyclic voltammetry at potential range -0.6 ~ 0.6 V, scan rate 100 mV s-1 in 0.1 mol L71 NaOH solution. The resulted modified electrode was characterized by cyclic voltammetry and scanning electron microscopy (SEM), which showed excellent electrocatalytic activity for the oxidation of H(2)0(2). The chronoamperometric detection of H(2)0(2) was carried out at 0.6 V in phosphate buffer solution pH 7.38 containing 0.1 mol L71 KC1 and the linear relationship of response current on H(2)0(2) concentration was obtained in the range from 4. Ixl0~10 to lxl0~-mol L-1 with a minimum detectable concentration of 3xl0~10 mol L71 [S/N (signal noise ratio) = 3]. The response time of the electrode to achieve 95% of the steady-state current was < 2 s. No measurable reduction in analytical performance of the modified electrode was found by storing the electrode in ambient conditions for 30 days. This modified electrode has many advantages such as simple preparation procedure, remarkable catalytic activity, good reproducibility and long term stability of signal response during hydrogen peroxide oxidation. The deposition of manganese dioxide on the surface of GC appears to be a highly efficient method for the development of a new class of sensitive, stable and reproducible hydrogen peroxide electrochemical sensor.
Determination of vitamin B6 (pyridoxine) in pharmaceutical preparations by cyclic voltammetry at a copper(II) hexacyanoferrate(III) modified carbon paste electrode
Teixeira, Marcos F. S.;Segnini, Aline;Moraes, Fernando C.;Marcolino-Júnior, Luiz H.;Fatibello-Filho, Orlando;Cavalheiro, éder T. G.;
Journal of the Brazilian Chemical Society , 2003, DOI: 10.1590/S0103-50532003000200021
Abstract: a copper(ii) hexacyanoferrate(iii) (cuhcf) modified carbon paste electrode was used for the electroanalytical determination of pyridoxine (vitamin b6) in pharmaceutical preparations, using cyclic voltammetry. diverse parameters were investigated for the optimization of the sensor response, such as composition of the electrode, electrolytic solution, effect of ph, scan rate of potential and interferences. the optimum conditions were found at an electrode composition of 20% cuhcf, 55% graphite and 25% mineral oil (m/m) in an acetate buffer (ph 5.5) containing 0.05 mol l-1 of nacl. the range of determination of pyridoxine was from 1.2 x 10-6 to 6.9 x 10-4 mol l-1. the procedure was successfully applied to the determination of vitamin b6 in formulation preparations. the cuhcf modified carbon paste electrode gave results comparable to those obtained using spectrophotometry.
Determination of vitamin B6 (pyridoxine) in pharmaceutical preparations by cyclic voltammetry at a copper(II) hexacyanoferrate(III) modified carbon paste electrode  [cached]
Teixeira Marcos F. S.,Segnini Aline,Moraes Fernando C.,Marcolino-Júnior Luiz H.
Journal of the Brazilian Chemical Society , 2003,
Abstract: A copper(II) hexacyanoferrate(III) (CuHCF) modified carbon paste electrode was used for the electroanalytical determination of pyridoxine (vitamin B6) in pharmaceutical preparations, using cyclic voltammetry. Diverse parameters were investigated for the optimization of the sensor response, such as composition of the electrode, electrolytic solution, effect of pH, scan rate of potential and interferences. The optimum conditions were found at an electrode composition of 20% CuHCF, 55% graphite and 25% mineral oil (m/m) in an acetate buffer (pH 5.5) containing 0.05 mol L-1 of NaCl. The range of determination of pyridoxine was from 1.2 x 10-6 to 6.9 x 10-4 mol L-1. The procedure was successfully applied to the determination of vitamin B6 in formulation preparations. The CuHCF modified carbon paste electrode gave results comparable to those obtained using spectrophotometry.
CO adsorption on electrode of Pt nanoparticles investigated by cyclic voltammetry and in situ FTIR spectroscopy
Wei Chen,Yanxia Jiang,Shigang Sun,
CHEWWei
,JIANGYanxia

科学通报(英文版) , 2003,
Abstract: Pt nanoparticles were prepared by the chemical reduction method. The average diameter of Pt nanoparticles was determined to be 2.5 nm by TEM. The electrochemical properties of Pt nanoparticles were studied by cyclic volt-ammetry. In comparison with massive Pt, the oxidation cur-rent peak of CO adsorbed on Pt nanoparticles is broader. Twin adsorbates of CO on Pt nanoparticles were determined by in situ FTIRS for the first time. It has revealed that the linear and twin-bonded CO can be converted into bridge-bonded CO with the variation of electrode potential. A series of special properties of Pt nanoparticles, such as enhanced IR absorption of CO adsorbates, were also ob-served.
Electrocatalysis of a SiC particle-modified glassy carbon electrode for the oxidation of adrenaline in a KRPB physiological solution
ZHANG-YU YU,DE-SHENG KONG,SHU-XIN WU,LEI WANG
Journal of the Serbian Chemical Society , 2005,
Abstract: The electrocatalytic properties of a SiC particle-modified glassy carbon electrode (MGC) for adrenaline oxidation were studied by cyclic voltammetry, double- potential slep chronoculometry and electrochemical impedance spectroscopy in a pH 7.4 physiological Kres–Ringer phosphate buffer (KRPB) solution. It was shown that modification of the electrode with SiC particles has a marked electrocatalytic effect on the electrochemical reaction of adrenaline, i.e., the activity and the reversibility of the MGC electrode were significantly improved compared to an ummodified electrode. This was attributed to the adsorption effect of the electroactive adrenaline molecules on the MGC electrode surface.
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