• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.10 no.2
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• pp.331-336
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• 2005

• 대한생식의학회:학술대회논문집
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• 2005.11a
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• pp.134-135
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• 2005

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2131-2133
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• 2004

모세관 전기영동 및 전기화학적 검출 시스템을 마이크로 시스템에 적용하여 ITO 유리기판과 polydimethylsiloxane (PDMS)로 제작하였다. 제작된 모세관 전기영동 및 전기화학적 검출 시스템은 일회용으로 사용가능하며 전기화학적 검출에 아주 적합한 특성을 보인다. 모세관 전기영동 및 전기화학적 검출 시스템은 주입과 분리 채널 (80 ${\mu}m$ 폭 ${\sim}$ 40 ${\mu}m$ 깊이)을 가진 PDMS 층과 유리기판 위에 검출 전극으로 사용되는 ITO가 형성된 층으로 구성된다. PDMS 층과 ITO 유리 기판은 UV-$O_3$ cleaner를 사용하여 접합하였다. 완충용액은 10 mM 2-(N-morpholino)ethanesulfonic acid (MES)를 사용하였고 분석물질은 1 mM 농도의 dopamine과 1 mM 농도의 catechol을 사용하였다. 60 V/cm 전계로 주입 및 분리를 하였으며 작업전극과 기준전극 간의 전위는 +600 mV로 유지하며 분석물질의 농도에 비례하는 전류량법으로 측정하였다. 전기화학적 검출 회로는 천기영동 전계의 간섭으로부터 분리하였다. 10 mM MES 완충용액에서 바탕 전류의 크기가 ${\sim}$10 pA 일 때 측정전류 값은 10 nA이다. 측정된 피크 값은 기존의 Au 전극과 비교하여 선택성, 감도, 분해능이 유사한 특성을 보여준다.

• Analytical Science and Technology
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• v.10 no.3
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• pp.216-224
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• 1997

In the study of cyclic voltammogram of rubeanic acid, rubeanic acid has two reduction peaks; first peak is similar with that of $S^{2-}$ and thiourea, which is conceded to by HgS, second peak is very weak and unidentified. The study also describes the differential pulse cathodic stripping voltammetric method for the determination of rubeanic acid. The followings were optimal conditions of rubeanic acid for the study : 0.05M borate buffer solution(pH 10.0) ; an accumulation potential of -0.30V(vs. Ag/AgCl); accumulation time of 120sec. : scan rate of 10mV/sec. The detection limit of trace analysis shows $2.7{\times}10^{-8}M$ of rubeanic and at optimal conditions.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.18-22
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• 1994

This study was designed to investigate the method of the simultaneous determination of water-soluble vitamins (thiamine, ascorbic acid, riboflavin, folic acid, cyanocobalamine, pyridoxin, nicotinic acid) by free soloution capillary electrophoresis. Factors affecting on the separation were pH of the buffer, applied voltage and temperature. On-column detection at 254 nm allowed accurate and reproducible determination of these compounds. All these compounds were separated within ca. 8 min with fused silica capillary at 20 kV.

• 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.

• KSBB Journal
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• v.24 no.3
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• pp.253-258
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• 2009

In this study, the optimization of fabrication conditions was accomplished to make immuno-strip biosensor by the combination of enzyme linked immunosorbent assay (ELISA) and immuno-chromatographic strip techniques for the detection of Escherichia coli O157 : H7. Optimal fabrication conditions of capture antibody concentration, detection antibody concentration, and additive composition of running buffer solution were determined. Optimal concentration was determined as 1.0 mg/mL for both of capture antibody and detection antibody. A composition of 0.5% Tween20 and 3% BSA were selected as optimal additive for buffer solution to prevent non-specific binding.

• Journal of the Korean Electrochemical Society
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• v.10 no.1
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• pp.14-19
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• 2007

The corrosion and passivation of copper was investigated with the copper rotating disk electrode(Cu-RDE) in borate buffer solution. It has been observed with the mixed potential theory that the corrosion potential for the rotation rate increase under the convective diffusion condition was increased. It was suggested that the chemical intermediates and product 13. the copper oxidation were $Cu(OH)_{ads},\;{Cu(OH)_2}^-,\;Cu_2O,\;Cu(OH)_2,\;and\;CuO$.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.9-16
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• 2014

In a borate buffer solution, the growth kinetics and the electronic properties of passive film on nickel were investigated, using the potentiodynamic method, chronoamperometry, and single- or multi-frequency electrochemical impedance spectroscopy. The oxide film formed during the passivation process of nickel has showed the electronic properties of p-type semiconductor, which follow from the Mott-Schottky equation. It was found out that the passive film ($Ni(OH)_2$) of Ni formed in the low electrode potential changes to NiO and NiO(OH) while the electrode potential increases.

• Journal of the Korean Chemical Society
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• v.61 no.6
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• pp.320-327
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• 2017

In a borate buffer solution, the growth kinetics and the electronic properties of passive film on cobalt were investigated, using the potentiodynamic method, chronoamperometry, and single-frequency electrochemical impedance spectroscopy. It was found out that the unstable passive film ($Co(OH)_2$) and CoO of Co formed in the low electrode potential changes to $Co_3O_4$ and CoOOH while the electrode potential increases. And the composition of the passive films was varied against the applied potential and oxidation time. The oxide film formed during the passivation process of cobalt has showed the electronic properties of p-type semiconductor, which follow from the Mott-Schottky equation.