• Bulletin of the Korean Chemical Society
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• 제10권6호
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• pp.485-488
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• 1989

A carbon paste coated-wire ion-selective electrode for chloride (carbon chloride-CWE) was constructed using epoxy resin, ion-exchanger and carbon powder as a polymer membrane. Its utility, the composition of a polymer membrane, the response characteristics, and the selectivity were examined and applied to the environmental water analysis. The carbon chloride-CWE was prepared using a silver wire, which was covered with silver chloride and then coated with epoxy resin into which chloride ion-exchanger and carbon powder were previously incorporated in advance. The response of the carbon chloride-CWE was Nernstian for $1.0{\times}10^{-2}-2{\times}10^{-5}$ M chloride and the useful pH range from $10^{-2} M Cl- to 10^{-4} M Cl^-$ was 3.0-9.0. Furthermore, the selectivity of chloride over iodide, bromide, and cyanide was much improved compared with those for a solid state epoxy body chloride electrode and a liquid membrane chloride electrode. The carbon chloride-CWE was applied to determine Cl^-$ in tap and ground water. The obtained results were in good agreement with those by the established methods such as spectrophotometric or other chloride-selective electrode methods.

• 분석과학
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• 제8권4호
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• pp.611-615
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• 1995

The design of appropriate chemically modified electrodes should allow development of new voltammetric measurement schemes with enhanced selectivity and sensitivity. Microorganism like algae has high ability to trap toxic and heavy metal ions and different affinities for metal ions. A copper(II) ion-selective carbon paste electrode was constructed by incorporating alga Anabaena into a conventional carbon paste mixture, and then the film of 10% Nafion was coated to avoid the swelling of the electrode surface. Copper ion could be deposited at the 25% algamodified electrode for 15 min without the applied potential while stirring the solution by only immersing the electrode in a buffer (pH 4.0) cot1taining copper(II). Temperature was controlled at $35^{\circ}C$. After preconcentration was carried out the electrode was transferred to a 0.1 M potassium chloride solution and was reduced at -0.6 volt at $25^{\circ}C$. The differential pulse anodic stripping voltammetry was employed. A well-defined oxidation peak could be obtained at -0.1 volt (vs SCE). In five deposition / measurement / regeneration cycles, the responses were reproducible and relative standard deviations were 3.3% for $8.0{\times}10^{-4}M$ copper(II). Calibration curve for copper was linear over the range from $2.0{\times}10^{-4}M$ to $1.0{\times}10^{-3}M$. The detection limit was $7.5{\times}10^{-5}M$. Studies of the effect of diverse ions showed that the coexisting metal ions had little or no effect for the determination of copper. But anions such as cyanide. oxalate and EDTA seriously interfered.

• 분석과학
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• 제12권2호
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• pp.171-175
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• 1999

Carbon paste electrodes, modified with podands containing more than two sulfur atoms, have been employed for the voltammetric determination of Ag(I) ion from aqueous solution. The voltammetric response was characterized with respect to paste composition, preconcentration method, kind of anion, variation of pH, Ag(I) ion concentration, and possible interferences. Linear calibration curves were obtained for Ag(I) ion concentration ranging from $1.0{\times}10^{-6}$ to $9.0{\times}10^{-5}M$, and detection limit was $5.0{\times}10^{-7}M$.

• 분석과학
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• 제15권1호
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• pp.91-95
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• 2002

Carbon paste electrodes, modified with 5,6,14,15-dibenzo-1,4-dioxa-8,12-diazacyclopentadeca-5,14-diene containing different ligating atoms of oxygen and nitrogen, have been employed for the voltammetric determination of Ag(I) ion from aqueous solution. The voltammetric response was characterized with respect to paste composition, preconcentration method, kind of anion, variation of pH, Ag(I) ion concentration, and possible interferences. Linear calibration curves were obtained for Ag(I) ion concentration ranging from $3.0{\times}10^{-6}M$ to $8.0{\times}10^{-5}M$, and detection limit was $8.5{\times}10^{-7}M$.

• 전기화학회지
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• 제17권2호
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• pp.130-137
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• 2014

본 연구에서는 스크린 프린팅 방법을 이용하여 이산화납($PbO_2$)/탄소 반죽 전극을 제작하고, 이를 전기화학 방법의 과일 천연당(포도당, 자당, 과당) 측정용 센서로 이용하였다. 이산화납/탄소 반죽전극은 탄수화물과 같은 유기화합물의 전기화학적 산화촉매 신호를 측정함으로써 효소를 사용하지 않고도 당의 측정이 가능하다. 또한 측정 시 심각한 방해작용을 하는 아스코르브산(ascorbic acid)은 Nafion 막을 전극표면에 도입함으로써 효과적으로 감소시켰다. 최적화된 Nafion/이산화납/탄소 반죽 전극은 사람이 느끼는 상대당도(과당>자당>포도당)와 유사하게 각 당에 대한 감응신호를 나타내었다.

• 분석과학
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• 제16권6호
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• pp.504-508
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• 2003

A carbon paste electrode was constructed with peroxidase extracted from Horseradish and the variation of the response of the sensor with pH was investigated. Current profiles showed two highest sensitivities at two pH values respectively. In addition, two bands were observed in the electrophoretic expansion. A coincidence of the two experimental results added support to the possibility that the biosensor has two different isozymes. Assuming that current profiles are the sum of two gaussians, we deconvoluted them and determined the optimum pH of peroxidase isozymes.

• 대한화학회지
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• 제38권10호
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• pp.734-740
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• 1994

Ag(I) 이온의 정량을 위해 cinchonidine으로 변성된 탄소 반죽전극(carbon paste electrode : CPE)을 제작하여 순환 전압-전류법 및 시차펄스 전압-전류법(differential pulse voltammetry:DPV)을 사용하여 정량하였다. Ag(Ⅰ)이온의 검출한계는 순환 전압-전류법으로는 $1.0 {\times}10^{-6}$ M, 시차펄스 전압-전류법에서는 $8.0{\times}10^{-9}$ M (${\pm}$0.6%)이었다. Ag(I)이온의 최적 분석조건은 pH 7, 담그는 시간은 20분, 그리고 탄소 분말에 대한 cinchonidine의 함량은 50% (w/w)였다. 방해 작용이 예상되는 다른 여러 종류의 금속 이온에 대하여 실험한 결과 Hg(II)이온을 제외한 다른 금속 이온 용액에서는 25% Ag(I) 이온 전류 크기가 감소하였다. 또한 Mn(II)이온이 존재할 때 pH 9에서 큰 방해 작용을 나타내었다.

• 공업화학
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• 제22권1호
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• pp.114-118
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• 2011

미네랄 오일을 결합재로 사용하는 탄소반죽전극은 효소의 특성 연구 분야에서 효과적으로 활용되고 있으나 전극이 기계적 경도가 없으므로 실용화의 가능성은 없다. 본 실험실에서는 톨루엔에 녹인 고무 용액이 탄소가루의 결합재로 사용될 때 탄소반죽의 기계적 물성이 얻어지는 것을 확인하였다. 클로로프렌 고무 용액을 이용하여 만든 전극이 정량적인 전기화학적 행동을 보이는지 확인하기 위하여 여러 가지 속도론적 파라메터 즉 대칭인자($\alpha$, 0.28), 교환전류밀도 ($i_0$, $4.06{\mu}A/cm^2$), 이중층의 축전용량($C_d$, $2.11{\times}10^{-3}F$), Michaelis 상수($K_M$, $2.45{\times}10^{-3}M$), 시간상수(${\tau}_B$, 0.077 sec) 등을 구하였다. 이 실험적 사실들은 클로로프렌 고무가 탄소반죽전극의 실용화에 전망 좋은 결합재임을 입증하였다.

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.948-952
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• 2003

New approach for the determination of Ag(I) ion was performed by using a carbon paste electrode (CPE) containing N,N'-Diphenyl oxamide (DPO) with anodic stripping voltammetry. The CMEs have been prepared by making carbon paste mixtures containing an appropriate amount of DPO salt coated onto graphite particles to analyze trace metal ions via complexation followed by stripping voltammetry. Various experimental parameters affecting the response, such as pH, deposition time, temperature, and electrode composition, were carefully optimized. Using differential pulse anodic stripping voltammetry, the logarithmic linear response range for the Ag(I) ion was 1.0 × $10^{-7}$ - 5.0 × $10^{-9}$ M at the deposition time of 10 min, with the detection limit was 7.0 × $10^{-10}$ M. The detection limit adopted from anodic stripping differential pulse voltammetry was 7.0 × $10^{-10}$ M for silver and the relative standard deviation was ± 3.2% at a 5.0 × $10^{-8}$ M of Ag(I) ion (n = 7). The proposed electrode shows a very good selectivity for Ag(I) in a standard solution containing several metals at optimized conditions.

• 전기화학회지
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• 제2권4호
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• pp.227-231
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• 1999

Carbon paste전극을 백금도금 한 후 이 전극을 사용한 일회용 전류법 glucose센서를 제작하였다. 전극에 시료용액을 가한 후, voltammetry을 이용하여 본 센서의 감응성을 연구하였다. screen printing된 carbon paste전극 표면 위에 전기도금 방법으로 도입된 백금은 센서의 분석성능과 mediator의 전기 화학적 가역성을 크게 향상시켜 준다. 제작된 센서가 $[Fe(CN)_6]^{4-/3-}$에 대한 heterogeneous rate constant는 $1.45\times10^{-2}cm{\cdot}s^{-1}$이며, 이 센서는 적용전위 0.3V vs. Ag/AgCl에서 glucose에 대한 좋은 감응성을 보여주었다. 이 때 glucose에 대한 Michaelis-Menten상수는 24.5mM이다. 일회용 glucose 스트립 센서의 분석성능을 평가하기 위하여 NOVA S.P. Ultra M analyzer와 비교실험을 수행하였다. 이 때 시료용액으로서 $80\~297 mg/dL$ 범위의 glucose를 함유하고 있는 30여 종류의 혈청을 사용하였고, 상관계수는 0.983으로서 정밀도와 정확도가 비교적 우수함을 보여주었다.