• Analytical Science and Technology
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• v.7 no.2
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• pp.133-140
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• 1994

The determination of sex hormones by adsorpive stripping voltammetry in $1.0{\times}10^{-2}M$ sodium hydroxide as supporting electrolyte has been investigated in the conditions as follows : 240sec. for deposition time, -0.80 volts deposition potential, medium size mercury drop, and 20mV/sec scan rate. Calibration curve has shown a linearlity in the range of $5.0{\times}10^{-9}M$ to $8.0{\times}10^{-7}M$ and the detection limits have been $8.0{\times}10^{-10}M$ for progesterone and $1.4{\times}10^{-9}M$ for testosterone propionate. This method has shown such a good sensitivity even in dilute solution that has been use full for analyzing sex hormones in medical supplies without interference of additives.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1182-1186
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• 2010

A novel poly(safranine)-modified electrode has been constructed for the determination of 4-nitrophenol (4-NP) in natural water sample. The electrochemical behavior of poly(safranine) film electrode and its electrocatalytic activity toward 4-NP were studied in detail by cyclic voltammetry (CV) and adsorptive linear stripping voltammetry (LSV). All experimental parameters were optimized and LSV was proposed for its determination. In optimal working conditions, the reduction current of 4-NP at this poly(safranine)-modified electrode exhibited a good linear relationship with 4-NP concentration in the range of $8.0{\times}10^{-8}$ to $4.0{\times}10^{-5}mol\;L^{-1}$. The detection limit was $3.0{\times}10^{-8}mol\;L^{-1}$. The high sensitivity and selectivity of the sensor were demonstrated by its practical application for the determination of trace amounts of 4-NP in natural water and fruit samples.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.186-190
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• 1995

A simple procedure, readily available at low cost with a sensitivity sufficient to determine trace levels of iron in seawater is proposed, which utilizes adsorptive accumulation of the iron/catechol complex on the mercury drop electrode in a borate medium of pH 8.0. Optimal conditions include a solution concentration of 2 mM catechol, 2.5 mM borate and a pH of 8.0, an accumulation potential of - 0.25 V is applied for 1∼3 min, and the potential scan is in the differential pulse mode. The limit of detection is 1.5 nM Fe using a preconcentration time of 3 min. The interference from copper can be eliminated and baseline slope is greatly improved, because its peak is well separated from that of iron in the proposed medium.

• Journal of the Korean Chemical Society
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• v.35 no.2
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• pp.151-157
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• 1991

A sensitive stripping voltammetric study of the complex of indium with 8-hydroxyquinoline at a hanging mercury drop electrode was investigated in 0.1M acetate buffer solution. The effects of various analytical conditions on the reduction peak current of the adsorbed complex were discussed. Optimal analytical conditions were found to be the ligand concentration of $2 {\times}10^{-5}$M, solution pH 4.75, scan rate of 10 mV/s, deposition potential of -0.450V, a deposition time of 90 second. Interferences by other trace metals and Triton X-100 were also discussed. Detection limit was 0.2 ppb of indium after 90 sec. Deposition time, and the relative standard deviation(n = 10) at 4 ppb was 3.2%.

• Analytical Science and Technology
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• v.16 no.3
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• pp.198-205
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• 2003

The ammonium salt of nitrosophenylhydroxylamine, called cupferron, has been used not only as the ligand but also as an oxidizing agent for adsorptive catalytic stripping voltammetry (AdCtSV). Cyclic voltammetry was used for elucidating the electrochemical behavior of Os-cupferron complex in 1 mM phosphate buffer. The optimal conditions for osmium analysis were found to be 1 mM phosphate buffer solution (pH 6.0) containing 0.1 mM cupferron at scan rate of 100 mV/s. By using the plot of reduction peak currents of linear scan voltammograms vs. osmium concentration, the detection limit was $1.0{\times}10^{-7}M$.

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.37-47
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• 1988

The electrochemical behavior of 2-Amino-1-cyclopentene-1-dithiocarboxylate (acdc) was investigated by the use of polarography, cyclic voltammetry and cathodic stripping voltammetry at glassy carbon electrode. In this study, it was found that the dimer of the acdc was deposited on the glassy carbon electrode via one-electron oxidation process at +0.25V vs. SCE. The ring formation between two dithio group occurs along with the elimination of one sulfur atom. The elimination of sulfur atom occurs via two electron oxidation process at +0.8V vs. SCE. The most sensitive cathodic stripping peak due to the formation of the dimer was observed at -0.85V vs. SCE. The peak relationship between current and concentration was fairly linear in the range of 3${\times}10^{-5}{\sim}1.0{\times}10^{-6}$M. The preconcentration procedure enhanced the sensitivity about 100 times for the analysis of acdc using diffusion current. Detection limit was found to be $2.5{\times}10^{-7}$M and relative standard deviation was ${\pm}$4.1 % at $5.0{\times}10^{-6}$M DC polarography.