• 대한화학회지
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• 제45권4호
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• pp.298-303
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• 2001

생체시료에 함유된 미량수은을 유리질 탄소전극을 사용하는 양극 벗김 네모파 전압-전류법으로 정량하였다. 생체시료는 HNO3/H2SO4 산혼합용액으로 삭히고, KMnO4를 가하여 산화시켰다. 수은의 검출한계는 석출전위, 시 간, pH, 그리고 용액을 저어주는 속도 등에 크게 영향을 받았다. 1.0 volts vs. Ag/AgCl에서 400rpm으로 저어주면서 240 sec 동안 석출시켰을 경우, 검출한계는 0.5 ppb 이하였다. 흰쥐에 대한 수은의 생체 축적량은 신장과 간에서 높았고, 뇌에서는 매우 낮았다.

• 대한화학회지
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• 제50권3호
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• pp.208-215
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• 2006

간편하게 만들어진 흑연연필심 작업전극을 사용한 순환전압전류법과 사각파형 벗김 전압 전류법으로 살충제 페니트로치온을 정량하였다. 최적분석조건을 연구한 결과 기존의 전기화학적 분석법들 보다 정밀하고 낮은 검출한계에 도달하였으며 이들 조건은 다음과 같다. 수소이온농도: 3.7 pH, 벗김 사각파형 주파수: 500 Hz, 벗김 사각파형 증폭률: 0.1V, 벗김파형 상승전위: 0.005V, 석출전위: -0.9V, 석출시간: 500초에서 벗김전압전류법과 순환전압전류법의 페니트로치온 농도 검출한계는: 6.0 ngL1 (2.164×1011 molL-1) 이었다. 상대표준편차는 10 ugL-1을 15번 반복측정하여 0.30%의 정밀도 였으며. 위 최적 조건에서 실시간 살아있는 세포에서 분석 응용하였다.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2499-2507
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• 2012

A novel and convenient electrochemical method has been developed for sensitive determination of melamine (MEL) using ascorbic acid (AA) as the recognition element. The working electrode employed in this method was modified with the nanocomposite of hydroxyapatite/carbon nanotubes to enhance the current signal of recognition element. The interaction between MEL and AA was investigated by fourier transform infrared spectroscopy and cyclic voltammetry, and the experimental results indicated that hydrogen bonding was formed between MEL and AA. Because of the existing hydrogen bonding and electrostatic interaction, the anodic peak current of AA was decreased obviously while the non-electroactive MEL added in. It illustrated that the MEL acted as an inhibitor to the oxidation of AA and the decreasing signals can be used to detect MEL. Under the optimal conditions, the decrease in anodic peak current of AA was proportional to the MEL concentrations ranging from 10 to 350 nM, with a detection limit of 1.5 nM. Finally this newly-proposed method was successfully employed to detect MEL in infant formula and milk, and good recovery was achieved.

• Toxicological Research
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• 제29권4호
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• pp.293-298
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• 2013

A method of detecting lead was developed using square wave anodic stripping voltammetry (SWASV) with DNA-carbon nanotube paste electrode (CNTPE). The results indicated a sensitive oxidation peak current of lead on the DNA-CNTPE. The curves were obtained within a concentration range of 50 $ngL^{-1}-20mgL^{-1}$ with preconcentration time of 100, 200, and 400 sec at the concentration of $mgL^{-1}$, ${\mu}gL^{-1}$, and $ngL^{-1}$, respectively. The observed relative standard deviation was 0.101% (n = 12) in the lead concentration of 30.0 ${\mu}gL^{-1}$ under optimum conditions. The low detection limit (S/N) was pegged at 8 $ngL^{-1}$ ($2.6{\times}10^{-8}M$). Results showed that the developed method can be used in real-time assay in vivo without requiring any pretreatment and pharmaceutical samples, and food samples, as well as other materials requiring water source contamination analyses.

• 한국약용작물학회지
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• 제7권1호
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• pp.11-15
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• 1999

국내에서 재배 수확되는 명일엽에 지역별, 부위별로 게르마늄 함량을 네모파 산화전극 벗김전압 전류법을 이용하여 조사한 결과 재배된 지역에 따라 게르마늄의 함량이 공시재료간 잎은 3.8배 정도, 줄기는 5배 정도였다. 명일옆(明日葉)의 채취부위별 게르마늄 함량은 잎부분에서 386ppm로 가장 높았으며 줄기에서 29ppm으로 13.3배 잎에서 더 높았다.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1125-1129
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• 2004

This work assesses the potential of natural Analcime Zeolite as an adsorbent for preconcentration of lead (II) traces. Lead is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol by column method with Analcime in the pH range of 5-6.5 and 2 mL $min^{?1}$ flow rate. Lead was removed from the column with 10.0 mL of 4 M hydrochloric acid and was determined by anodic stripping differential pulse voltammetry. 0.5ppb detection limit was obtained and linear dynamic range was 3 to $1.2{\times}10^5$ ppb in final solution with correlation coefficient of 0.999 and relative standard deviation of ${\pm}$ 1.2% (for eight replicate determination of 2.5 ${\mu}g\;mL^{?1}$ of lead). Various parameters such as the effect of pH, flow rate, instrumental conditions and interferences of some ions on the determination of lead have been studied in detail for optimization of conditions. The method was successfully applied for determination of lead in various samples.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.845-849
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• 2010

A gold nanoparticles modified carbon paste electrode (GN-CPE) has been used for the determination of atenolol (ATN) in drug formulations by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronocoulometric methods. The results revealed that the modified electrode shows an electrocatalytic activity toward the anodic oxidation of atenolol by a marked enhancement in the current response in buffered solution at pH 10.0. The anodic peak potential shifts by -80.0 mV when compared with the potential using bare carbon paste electrde. A linear analytical curve was observed in the range of $1.96\;{\times}\;10^{-6}$ to $9.09\;{\times}\;10^{-4}\;mol\;L^{-1}$. The detection limit for this method is $7.3\;{\times}\;10^{-8}\;mol\;L^{-1}$. The method was then successfully applied to the determination of atenolol in tablets and human urine. The percent recoveries in urine ranged from 92.0 to 110.0%.

• Journal of Electrochemical Science and Technology
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• 제8권4호
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• pp.307-313
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• 2017

In this paper we report an electrochemical sensor based on ZnO-functionalized graphene oxide nanocomposite (ZnO-GO) for the sensitive determination of the cabergoline. Cabergoline electrochemical behaviors were investigated by cyclic voltammetry (CV), chronoamperometry (CHA) and differential pulse voltammetry (DPV). The modified electrode shows electrocatalytic activity toward cabergoline oxidation in phosphate buffer solution (PBS) (pH 7.0) with a reduction of the overpotential of about 180 mV and an increase in peak current. The DPV data showed that the obtained anodic peak currents were linearly dependent on the cabergoline concentrations in the range of $1.0-200.0{\mu}M$, with the detection limit of $0.45{\mu}M$. The prepared electrode was successfully applied for the determination of cabergoline in real samples.

• 한국환경과학회지
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• 제19권8호
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• pp.941-949
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• 2010

The three electrode system was used to detect the pesticide fenitrothion ($C_9H_{12}NO_5PS$. MW=277.24) using cyclic voltammetry (CV) and square wave anodic stripping voltammetry (SWASV). The working electrode was mercury immobilized on a carbon nanotube paste electrode (Hg-CNTPE). At the optimized condition, the limit of detection (LoD) was 0.6 ppt ($2.16{\times}10^{-12}\;M$), and the relative standard deviation was 0.035% (n=15). And there is more sensitive in detecting fenitrothion than common type carbon nanotube paste electrode. When it was implanted into the brain of live fish (carp), the existence of fenitrothion was measured without any destruction or damage of tissue.

• 한국응용과학기술학회지
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• 제29권3호
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• pp.443-449
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• 2012

A investigation of electrochemical analysis of antibiotics Neomycin ($C_{23}H_{46}N_6O_{13}$) was searched using electrochemical square wave (SW) stripping and cyclic voltammetry (CV) using working sensor of the modified carbon nanotube combination electrodes, optimum diagnostic parameters were searched by anodic stripping, final conditions were attained to working range of 1.0-14.0 ng/L, detection limit (S/N) was found to be 0.6 ng/L. The developed method was discovered to be fitting in quality control in the food, pharmaceutical and other manufacturing sectors.