• Title/Summary/Keyword: Stripping voltammetry

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Detection of Toxic Heavy Metal, Co(II) Trace via Voltammetry with Semiconductor Microelectrodes

  • Ly, Suw Young;Lee, Chang Hyun;Koo, Jae Mo
    • Toxicological Research
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    • v.33 no.2
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    • pp.135-140
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    • 2017
  • The cobalt (Co(II)) ion is a main component of alloys and considered to be carcinogenic, especially due to the carcinogenic and toxicological effects in the aquatic environment. The toxic trace of the Co(II) detection was conducted using the infrared photodiode electrode (IPDE) using a working electrode, via the cyclic and square-wave anodic stripping voltammetry. The results indicated a sensitive oxidation peak current of Co(II) on the IPDE. Under the optimal conditions, the common-type glassy carbon, the metal platinum, the carbon paste, and the carbon fiber microelectrode were compared with the IPDE in the electrolyte using the standard Co(II). The IPDE was found to be far superior to the others.

Electrochemical Assay of Neurotransmitter Glycine in Brain Cells

  • Ly, Suw-Young;Kim, Dong-Young
    • Bulletin of the Korean Chemical Society
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    • v.28 no.4
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    • pp.515-519
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    • 2007
  • Neurotransmitter glycine in the nano gram range was analyzed using a paste electrode (PE) in cyclic voltammetry (CV) and square-wave stripping voltammetry (SWSV). An anodic peak caused by oxidation of the glycine ion appeared at the 0.4 V (versus Ag/AgCl/KCl) potential in a 0.1 M NH4H2PO4 electrolyte solution. At optimized conditions, the working range of the SWSV and CV concentration was found to be 5-60 ngL-1 glycine; precision of R2 = 0.9816 (SWSV) and 0.9986 (CV); and detection limit of 0.65 ngL-1 (5.82 × 10-12 molL-1) (S/N = 3). The optimized conditions were applied to an assay in a fish brain tissue and a living brain cell in real time.

Diagnostic ex vivo assay of glucose in live cell using voltammetry

  • Ly, Suw Young;Leea, Chang Hyun
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1379-1385
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    • 2018
  • The hand held voltammetry systems searched diabetic assay using glucose sensor of fluorine nafion doped carbon nanotube electrode (FCNE). An inexpensive graphite carbon pencil was used as an Ag/AgCl reference and Pt counter electrode. Upon combining and using three electrode systems, optimum square wave (SW) stripping results were attained to 1.0-9.0 ug/L with 8 points. Statistic RSD precision was of 6.02 % with n=15 in 0.1 mg/L glucose. After a total of 200 second accumulation times, analytical detection limit of 0.8 ug/L was obtained. This developed technique was applied to urine samples from diabetic patients urine for fluid analysis, it was determined that the sensor can be used with a diagnostics in the ex vivo of live cells and non treated biological fluid.

Determination of Rhodium by Inverted Catalytic Hydrogen peak as Analytical peak (뒤집힌 촉매수소 전류 봉우리를 이용한 로듐의 정량)

  • Kwon, Young-Soon;Lim, Kyong-Hee
    • Analytical Science and Technology
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    • v.16 no.4
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    • pp.269-276
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    • 2003
  • A new type of stripping voltammetry, inverted catalytic stripping voltammetry $IC_tSV$, is introduced. The rhodium-formaldehyde complex in hydrochloric acid gives an inverted catalytic hydrogen peak (reduction current peak during positive-going scan). The characteristics of the inverted peak were studied. By using the peak as analytical peak the detection limit of $1.2{\times}10^{-10}M$ Rh (50s preconcentration) can be reached at the optimal conditions: 0.015% (W/V) HCHO-0.42 M HCl; accumulation potential, -1.1 V; scan rate, 100 mV/s.

Determination of Trace Strontium with o-Cresolphthaleoxon by Electroanalytical method (o-Cresolphthaleoxon을 이용한 스트론튬의 전기화학적 분석)

  • Choi, Won Hyung;Lee, Jin Sik;Kim, Do Hoon;Kim, Jae Soo
    • Analytical Science and Technology
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    • v.6 no.3
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    • pp.247-254
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    • 1993
  • Strontium can not be determined by conventional dc polarography method since it is very difficult to be reduced at the drop mercury electrode(DME) in aqueous solution. However the analytical sensitivity was improved by adsorptive stripping voltammetry in which electro-reduction of ligand in a complex formed between strontium and o-cresolphthaleoxone was performed. Strontium could be determined in range of $5{\sim}30{\mu}g/L$ concentration. This method was affected by coexistent alkali earth metal ions. Consequently ion exchange separation is recommended to analyze strontium in samples.

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Electrochemical Analysis of Spontaneous Reduction of Silver on Tape by Mechanochemical Activation (기계화학적 활성에 의해 테이프에 자발적으로 환원된 은의 전기화학적 분석)

  • Yun, Changsuk
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.5
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    • pp.1100-1105
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    • 2020
  • We investigated the driving force and the required charges for spontaneous reduction of metal nanoparticles (NPs) on a scotch tape induced by mechanochemical activation. The charges were analyzed based on anodic stripping voltammetry (ASV) of silver, which is proportional to the number of charge identities on the tape. The results supported that the driving force is mechanochemical radicals rather than ions in the light of the high charge density on the tape.

Adsorptive Stripping Voltammetry of Indium-Morin Complex (Indium-Morin 착물에 관한 흡착벗김전압전류법적 연구)

  • Se Chul Sohn;Tae Yoon Eom;Yeong Kyeong Ha;Ki-Suk Jung
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.506-511
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    • 1991
  • A sensitive adsorptive stripping voltammetric study was investigated on the complex of indium with morin at a hanging mercury drop electrode in 0.1 M acetate buffer (pH 3.20) solution. The adsorption phenomena were observed by differential-pulse voltammetry. The effects of various analytical conditions were discussed on the reduction peak current of the adsorbed complex on the surface of HMDE. Interferences by other trace metals and surfactant were also discussed. Detection limit was 2.6 nM of indium after 90 second deposition time, and the relative standard deviation (n = 7) at 4TEX>${\mu}g$/l indium was 2.0%.

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The study of Germanium analysis by Adsorption Stripping Voltammetry (흡착벗김 전압전류법을 이용한 게르마늄 분석에 관한 연구)

  • Yun, Young Ja;Jeong, David;Namgung, Mi Ok
    • Analytical Science and Technology
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    • v.8 no.2
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    • pp.171-179
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    • 1995
  • This is an analytical study of germanium by adsorption stripping squarewave voltammetry. Tannic acid was used as a ligand. The accumulation potential was -0.2V, accumulation time was carried out for 60 second under constant stirring, followed by a 20 second quiescent period, and frequency was 10Hz. A hanging mercury drop electrode was used as a working electrode and acetate buffer solution, pH=4.5, as supporting electrolyte. The proper conditions of ligand for germanium analysis was established. The effect of metal ions(lead, cupper, silicon, tin, gallium) on germanium peak was also studied.

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Real-time Assay of Toxic Lead in In Vivo Living Plant Tissue

  • Ly, SuwYoung;Kim, Nack Joo;Youn, Minsang;Kim, Yongwook;Sung, Yeolmin;Kim, Dohoon;Chung, Tackhyun
    • Toxicological Research
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    • v.29 no.4
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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.

Germanium(IV) Content in the Korean Angelica keiskei Koidz (국내산(國內産) 명일엽(明日葉)의 부위별 게르마늄 함량(含量))

  • Jeong, Seung-Il;Han, Wan-Soo
    • Korean Journal of Medicinal Crop Science
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    • v.7 no.1
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    • pp.11-15
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    • 1999
  • The uptake of germanium(Ge) by health foodstuffs was interesting because of a therapeutic effect of organic germanium. Germanium contents in different plant parts of the cultivated Korean Angelica keiskej Koidz in several growing districts were determined by square wave anodic stripping voltammetry. Experimental conditions in germanium determination from Angelica kejskej Koidz were as follows : deposition time; 20 sec, deposition potential; -0.9 volts vs Ag/AgCl, and frequency; 100 Hz in 0.1M\;HClO_4, supporting electrolyte solution at pH 2.43 containing $1.5\;{\times}\;10^5\;M$ pyrocatechol violet. Calibration curve showed a good lineality in the range of 0.4 ppb to 2.0 ppm and the detection limit was 0.08 ppb. There was a large difference in content according to growing districts ranging from 102 to 386ppm. Germanium content in leaf parts was much higher than that in stems.

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