• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.568-573
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• 2013

A selective and sensitive method for simultaneous determination of copper in blood by adsorptive differential pulse cathodic stripping voltammetry is presented. The procedure involves an adsorptive accumulation of Cu(II)-ETSC (4- ethyl-3-thiosemicarbazide) on a hanging mercury drop electrode, followed by a stripping voltammetry measurement of reduction current of adsorbed complex at about -715 mV. The optimum conditions for the analysis of copper (II) ion are : pH 10.3, concentration of 4-ethyl-3-thiosemicarbazide $3.25{\times}10^{-6}$ M and an accumulation potential of -100 mV. The peak current is proportional to the concentration of copper over the range 0.003-125 ng/mL with a detection limit of 0.001 ng/mL and an accumulation time of 60 s. Moreover, with the use of the proposed method, there is a considerable improvement in the detection limit, the linear dynamic range and the deposition time, compared with the methods of adsorptive stripping voltammetry for the determination of copper. The developed method was validated by analysis of whole blood certified reference materials.

• Analytical Science and Technology
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• v.10 no.2
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• pp.119-125
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• 1997

A stripping voltammetric procedure for determining ruthenium was developed, based on the adsorptive accumulation of ruthenium in the presence of hydrazine in acidic acetate buffer. After preconcentration of ruthenium compelex and reduction, the ruthenium-catalyzed hydrogen current at -0.84V was measured by differential pulse voltammetry. Optimal experimental conditions were found to be a stirred acetate buffer solution(pH 2.0) containing 0.01M acetate and 0.01M hydrazine, accumulation potential of -0.76V, and a scan rate of 5mV/s. The detection limit was $2{\times}10^{-9}M$ for a 7 min accumulation period. The possible interferences by other platinum group metals were also investigated.

• Analytical Science and Technology
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• v.6 no.5
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• pp.425-433
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• 1993

Adsorptive stripping voltammetric determination method of trace zirconium using oxine as a ligand was studied. Optimal conditions found to be $2.5{\times}10^{-3}M$ borax buffer solution(pH 8.5) containing oxine concentration of $4{\times}10^{-8}M$. Accumulation potential was -0.2V, accumulation time was 400sec and scan rate was 4mV/sec. Calibration plots for zirconium are linear over the range of $1{\sim}100{\mu}g/L$ in optimal condition.

• Analytical Science and Technology
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• v.14 no.6
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• pp.540-544
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• 2001

Determination of cyanide ion has been studied by adsorptive stripping voltammetry using hanging mercury electrode. Cyanide ion complexed with copper ion is adsorpbed on the electrode and oxidised at the positive potential scan. Optimal conditions of CN determination were found to be ; supporting electrolyte solution ; 0.1 M NaCl of ammonium buffer at pH 10, accumulation potential; -800 mV vs Ag/AgCl, accumulation time ; 300 s, scan rate ; 50mV/s. The linear concentration of cyanide ion was observed in the range $1{\times}10^{-8}$, $1{\times}10^{-7}M$. The detection limit(n/s=3) was $0.13{\mu}g/L$($5{\times}10^{-9}M$) with 3.5% RSD.

• Analytical Science and Technology
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• v.7 no.4
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• pp.461-469
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• 1994

Trace vanadium was determined by Adsorptive stripping voltammetry with HMDE in PIPES buffer solution. N-Benzoylphenylhydroxylamine was used as a ligand. The calibration curve of vanadium was linear over the range of $10{\sim}70{\mu}g/L$ on accumulation potential of +0.15V and on accumulation time of 10 sec. The various metal ions did not interfere with the determination of vanadium(V) in this case.

• Analytical Science and Technology
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• v.8 no.1
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• pp.25-32
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• 1995

Determination method of trace thioglycolate has been studied by adsorptive stripping voltammetry. Copper(II)-thioglycolate complex is adsorbed at the hanging mercury drop electrode and stripped during cathodic scan. Electrolyte was used pH 6.5 phosphate and pH 9.5 borate buffer solutions. Optimal conditions were a copper(II) concentration $1{\times}10^{-4}M$, an adsorption accumulation potential -0.2V, an adsorption accumulation time 60 sec and a scan rate 20mV/sec. A detection limit of $1{\times}10^{-9}M$ thioglycolate was obtained. The method was applied to the determination of thioglycolate in cold wave fluids and depilating creams.

• Analytical Science and Technology
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• v.10 no.2
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• pp.114-118
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• 1997

A stripping voltammetric scheme for the determination of osmium, based on the adsorptive accumulation of osmium in the presence of hydroxylamine, was described. Cyclic voltammetry was used to characterize the redox and interfacial processes. Optimal experimental conditions were found to be a stirred 0.05M hydroxylamine hydrochloride solution(pH 1.8), accumulation at -0.65V for 60s, and a differential pulse mode with a scan rate of 10mV/s. The detection limit was $6.3{\times}10^{-8}M$(12ppb) with the optimal condition.

• Analytical Science and Technology
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• v.8 no.3
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• pp.285-292
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• 1995

Uranium has variable oxidation states(${UO_2}^{+2}$, $UO^{+2}$, $U^{+4}$, $U^{+3}$) and 1-(2-Pyridylazo)-2-naphthol forms a very stable chelate with Uranium(${UO_2}^{+2}$). The determination method of Uranium(${UO_2}^{+2}$) in 0.1M Borate buffer(pH 7.10) has been investigated by adsorptive stripping voltammetry. The optimum conditions were PAN concentration of $5{\times}10^{-7}M$, accumulation potential of 0.00V(vs. Ag/AgCl) and accumulation time of 120sec. The calibration curve was linear over the range of $5{\sim}60{\mu}g/L$ and the various metal ions did not interfere with the determination Uranium(${UO_2}^{+2}$) except Cu(II) and Co(II).

• Journal of the Korean Chemical Society
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• v.41 no.5
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• pp.246-250
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• 1997

In the presence of optimum amounts of hydroxylamine, trace ruthenium(III) can be conveniently determined in acidic (boric) media by coupling catalytic hydrogen processes with adsorptive accumulation of the catalyst, using differential pulse voltammetry. Cyclic voltammetry was used to characterize the redox and interfacial processes. Optimal experimental conditions were found to be a stirred borate (0.015 M, pH 2.5) solution containing 0.55 M hydroxylamine, a preconcentration potential of - 0.70 V, and a scan rate of 5 mV/s. With a 7 min accumulation period the detection limit was 3${\times}$10-10 M. The possible interferences by other platinum group metals are investigated.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1035-1037
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• 1994

An ultrasensitive and selective stripping voltammetric scheme for the determination of rhodium is described. By the use of combined accumulation and catalytic effects in formaldehyde-hydrochloric acid medium, substantial improvement in the limit of detection can be obtained. Optimal experimental conditions were found to be 0.42 M hydrochloric acid solution containing 0.008${\%}$ formaldehyde, an accumulation potential of -0.70 V (vs. Ag/AgCl) and an accumulation time of 20 s. The stripping mode was differential pulse voltammetry. In these conditions the limit of detection lies at 2 ${\times}$ l0$^{-12}$ M (0.21 ppt). The relative standard deviation at 5 ${\times}$ l0$^{-11}$ M was 4.9${\%}$ (n=5). There were no serious interferences from other platinum group metal ions being the tolerable amounts more than 500 times that of rhodium.