• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.412-417
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• 2007

A simple prepared paste electrode (PE) of DNA immobilized on a carbon nanotube was utilized for monitoring the antibacterial agent oxytetracycline (OTC), using square-wave anodic stripping voltammetry (SWASV) and cyclic voltammetry (CV). Given these conditions, SWASV and CV working ranges were observed within 1-10 ngL-1 OTC. In the SWASV and CV for OTC concentrations of 0.1 mgL-1, the relative standard deviations (n=15) were 0.068 and 0.067, respectively. At the optimized condition, the detection limit was found to be 0.4 ngL-1 OTC. This method was applied to the hatchery fish tissue.

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.165-171
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• 2012

Here is implemented MATLAB program to analyze the characteristic curves of cyclic voltammetry which involves the multi-electron electrode reaction considered as key processes in electrochemical systems. For the electrochemical mass-transfer system, Fick's concentration equation subject to semi-infinite diffusion model for the boundary condition was discretized and solved by the explicit finite difference method. The resulting concentration values were converted into currents at each node by using Butler-Volmer equation. Based on the good agreement between the present numerical solution and the existing experimental results, effects of kinetic constants and CV scan rates on the reaction mechanism in multi-electron transfer processes were investigated effectively.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.515-519
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• 2007

Neurotransmitter glycine in the nano gram range was analyzed using a paste electrode (PE) in cyclic voltammetry (CV) and square-wave stripping voltammetry (SWSV). An anodic peak caused by oxidation of the glycine ion appeared at the 0.4 V (versus Ag/AgCl/KCl) potential in a 0.1 M NH4H2PO4 electrolyte solution. At optimized conditions, the working range of the SWSV and CV concentration was found to be 5-60 ngL-1 glycine; precision of R2 = 0.9816 (SWSV) and 0.9986 (CV); and detection limit of 0.65 ngL-1 (5.82 × 10-12 molL-1) (S/N = 3). The optimized conditions were applied to an assay in a fish brain tissue and a living brain cell in real time.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.346-351
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• 2020

The removal characteristics of copper (Cu) from electrochemical surface by voltage-activated reaction were reviewed to assess the applicability of electrochemical-mechanical polishing (ECMP) process in three types of electrolytes, such as HNO₃, KNO₃ and NaNO₃. Electrochemical surface conditions such as active, passive, transient and trans-passive states were monitored from its current-voltage (I-V) characteristic curves obtained by linear sweep voltammetry (LSV) method. In addition, the oxidation and reduction process of the Cu surface by repetitive input of positive and negative voltages were evaluated from the I-V curve obtained using the cyclic voltammetry (CV) method. Finally, the X-ray diffraction (XRD) patterns and energy dispersive spectroscopy (EDS) analyses were used to observe the structural surface states of a Cu electrode. The electrochemical analyses proposed in this study will help to accurately control the material removal rate (MRR) from the actual ECMP process because they are a good methodology for predicting optimal electrochemical process parameters such as current density, operating voltage, and operating time before performing the ECMP process.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.31-34
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• 2004

The electrochemical behavior of doxorubicin hydrochloride was investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). From CV and SWV studies of doxorubicin hydrochloride in the acetate buffers of various pH values, it was found that protons were involved in the reduction of the antibiotic at the $H^+/e^$- ratio at one ( $\DeltaEp/pH =-53 ∼ -61 mV at 23^{\circ}C$), proposing the electrochemical reduction of the quinone moiety in its anthraquinone aglycone. Its electrochemical behavior was pseudo-reversible in the acetate buffer of pH 3.5 by exhibiting the well-defined single cathodic and anodic waves and the ratio of $lp^a/lp^c$ at approximately one over the scan rates of 10∼100 mV/s. Fast and sensitive SWV showing a single peak of doxorubicin has been applied for its quantitative analysis using an acetate buffer of pH 3.5. A linearity was obtained when the peak currents (lp) were plotted against concentrations of doxorubicin in the range of $5.0\times10^{-7} M∼1.0\times10^{-5}$M with a detection limit of $1.0\times10^{-7}$ M.

• Journal of the Korean Applied Science and Technology
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• v.28 no.1
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• pp.15-21
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• 2011

Threelectrodes systems were used in stripping voltammetry (SW) and cyclic voltammetry (CV) instead of the expensive platinum and Ag/AgCl reference electrodes. Moreover, the electrolyte solution was used with deep seawater, which can reduce water pollution, is more eco-friendly, and has a lower cost. The analytical optimum parameters measured via CV and SW and with working ranges were obtained from 10 to 80 ug/L using fluorine immobilized on a graphite pencil electrode (FE). Under the optimum conditions, the analytical detection limit of 6.30 ug/LAu was obtained. The results of the study can be applied to diagnostic assay for natural minerals and human finger tissue.

• Journal of Electrochemical Science and Technology
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• v.13 no.3
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• pp.347-353
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• 2022

Agarose hydrogel, a solid electrolyte, was investigated voltammetrically in terms of transport properties and natural convection effects using a ferrocenyl compound as a redox probe. To confirm the diffusion properties of solute on the agarose interface, the diffusion coefficients (D) of ferrocenemethanol in agarose hydrogel were determined by cyclic voltammetry (CV) according to the concentration of agarose hydrogel. While the value of D on the agarose interface is smaller than that in the bulk solution, the square root of the scan rate-dependent peak current reveals that the mass transport behavior of the solute on the agarose surface shows negligible convection or migration effects. In order to confirm the reduced natural convection on the gel interface, scan rate-dependent CV was performed in the solution phase and on the agarose surface, respectively. Slow scan voltammetry at the gel interface can determine a conventional and reproducible diffusion-controlled current down to a scan rate of 0.3 mV/s without any complicated equipment.

• Journal of the Korean Chemical Society
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• v.46 no.3
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• pp.225-228
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• 2002

Poly-o-toluidine (POT) was chemically and electrochemically synthesized for the study of the electronic and steric effect of methyl substituents. It was found that the steric effect was dominant in POT. The IP 4.95 eV, EA 3.24 eV, Eg 1.71 eV of POT were found by the CV (Cyclic Voltammetry) and CCPSA (Constant Current Potentiometric Stripping Analysis).

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.157-160
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• 2007

The catalyst layer of a proton exchange membrane (PEM) fuel cell is a mixture of polymer, carbon, and platinum. The characteristics of the catalyst layer play critical role in determining the performance of the PEM fuel cell. This research investigates the role of catalyst layer composition using a Central Composite Design (CCD) experiment with two factors which are Nafion content and carbon loading while the platinum catalyst surface area is held constant. For each catalyst layer composition， polarization curves are measured to evaluate cell performance at common operating conditions, Electrochemical Impedance Spectroscopy (EIS), and Cyclic Voltammetry (CV) are then applied to investigate the cause of the observed variations in performance. The results show that both Nafion and carbon content significantly affect MEA performance. The ohmic resistance and active catalyst area of the cell do not correlate with catalyst layer composition, and observed variations in the cell resistance and active catalyst area produced changes in performance that were not significant relative to compositions of catalyst layers.

• Journal of Electrochemical Science and Technology
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• v.15 no.3
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• pp.427-435
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• 2024

Here we introduce a new method for characterizing the constant phase element (CPE) in electrochemical systems using cyclic voltammetry (CV), presenting an alternative to the conventional electrochemical impedance spectroscopy (EIS) approach. While CV is recognized for its diagnostic capabilities in electrochemical analysis, it traditionally encounters difficulties in accurately measuring CPE systems due to a lack of clear linearity with scan rates, unlike capacitors. Our research demonstrates a linear relationship between current and scan rate on a log-log plot, enabling the calculation of n and Y₀ values for CPE from the slopes of these linear relationships. For validation of our method, it is applied to two kinds of capacitors and the results agree with those measured by EIS. Although EIS is known to be accurate in measuring CPE systems, our alternative approach offers a timely and reasonably precise diagnostic tool, balancing between ease of use and accuracy, especially beneficial for preliminary assessments before conducting further in-depth analysis.