• Title/Summary/Keyword: adsorptive potential

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Determination of Cyanide Ion by Adsorptive Stripping Voltammetry (흡착벗김 전압전류법에 의한 시안화이온의 정량)

  • Cha, Ki-Won;Ko, Su-Jin;Kim, Jea-Kyun
    • 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.

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Determination of Ultra Trace Levels of Copper in Whole Blood by Adsorptive Stripping Voltammetry

  • Attar, Tarik;Harek, Yahia;Larabi, Lahcen
    • 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.

Adsorptive Stripping Voltammetrical Determination of Zirconium (흡착벗김 전압전류법적 지르코늄의 정량)

  • Choi, Won Hyung;Lee, Jin Sik;Kim, Do Hoon;Kim, Jong Cheol
    • 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.

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Heavy Metal Removal of Acrylic Acid-grafted Bacterial Cellulose in Aqueous Solution (아크릴산으로 그라프트된 미생물셀룰로오스의 수용액 내 중금속 흡착거동)

  • Ahn, Yeong-Hee;Choi, Yong-Jin
    • Journal of Environmental Science International
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    • v.23 no.8
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    • pp.1419-1428
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    • 2014
  • Electron beam-induced grafting polymerization was employed to prepare Acrylic acid-grafted bacterial cellulose (BC-g-AAc). BC-g-AAc as an adsorbent was applied to remove heavy metals (e.g., As, Pb, and Cd). This study examined followings; morphological change of surface, adsorptive behavior of BC-g-AAc, and interpretation of adsorptive kinetics. Specific surface areas of BC and BC-g-AAc were $0.9527m^2g^{-1}$ for BC and $0.2272m^2g^{-1}$ for BC-g-AAc, respectively as measured by BET nitrogen adsorption, revealing the morphological change of the surface of BC-g-AAc. Batch adsorption test was performed to investigate adsorptive behavior of BC-g-AAc in aqueous solution. The amounts of Pb and Cd adsorbed on BC-g-AAc were $69mg\;g^{-1}$ and $56mg\;g^{-1}$, respectively. However, As was not adsorbed on BC-g-AAc due to its neutral nature. Both the Benaissa model and the Kurniawan model were applied in the study to interpret adsorptive kinetics. From the value of correction coefficient ($R^2$), adsorptive kinetics of Pb and Cd were subjected to Kurniawan model referred to pseudo-second-order. Taken together, the results of this study show that BC-g-AAc has potential as a heavy metal (eg., Pb, Cd)-adsorbent made of an environmentally friendly material.

Determination of Vanadium with N-Benzoylphenylhydroxylamine by Adsorptive Stripping Voltammetry (N-Benzoylphenylhydroxylamine을 이용한 바나듐의 흡착벗김전압전류법적 정량)

  • Choi, Sung Yung;Choi, Won Hyung;Lee, Jin Sik;Lee, Sang Hoon;Lee, Yeong Sig
    • 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.

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Adsorptive Stripping Voltammetric Determination of Ruthenium (흡착 벗김법에 의한 루테늄 정량)

  • Hong, Tae-Kee;Kwon, Young-Soon;Czae, Myung-Zoon
    • 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.

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Determination of Thioglycolic acid in the presence of Copper(II) by Adsorptive Stripping Voltammetry (흡착 벗김 전압전류법에 의한 구리이온(II) 존재하에서 티오글리콜산의 정량)

  • Hong, Mi-Jeong;Kwon, Young-Sun
    • 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.

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In Vitro Cellular Uptake and Cytotoxicity of Paclitaxel-Loaded Glycol Chitosan Self-Assembled Nanoparticles

  • Park, Ji-Sun;Cho, Yong-Woo
    • Macromolecular Research
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    • v.15 no.6
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    • pp.513-519
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    • 2007
  • Self-assembled nanoparticles have great potential to act as vehicles for hydrophobic drug delivery. Understanding nanoparticle cellular internalization is essential for designing drugs intended for intracellular delivery. Here, the endocytosis and exocytosis of fluorescein isothiocyanate (FITC)-conjugated glycol chitosan (FGC) self-assembled nanoparticles were investigated by flow cytometry and confocal microscopy. The cellular internalization of FGC nanoparticles was initiated by nonspecific interactions between nanoparticles and cell membranes. Although adsorptive endocytosis of the nanoparticles occurred quickly, significant amounts of FGC nanoparticles were exocytosed, particularly in the early stage of endocytosis. The amount of exocytosed nanoparticles was dependent on the pre-incubation time with nanoparticles, suggesting that exocytosis is dependent on the progress of endocytosis. FGC nanoparticles internalized by adsorptive endocytosis were distributed in the cytoplasm, but not in the nucleus. In vitro cell cycle analysis demonstrated that FGC nanoparticles delivered paclitaxel into the cytoplasm and were effective in arresting cancer cell growth.

Research Progress of Antibiotic Pollution and Adsorption Materials in Aquatic environment

  • Zheng, Kun;Deng, ChengXun;Deng, Xu;Yu, ZhiMin
    • Journal of Urban Science
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    • v.8 no.2
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    • pp.1-5
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    • 2019
  • China is the great powers of use and production of antibiotics.The current process of sewage treatment plants can not effectively remove antibiotics in water. Chinese scholars have detected different kinds of antibiotics in major waters of the country, which have potential harm to human body. Among all kinds of antibiotic treatment technologies, adsorption removal technology has the advantages of simple operation, low cost and high removal efficiency. It is a widely concerned antibiotic removal technology. However, at present, few materials have been put into practical application, and more materials with low cost and high efficiency need to be found. Different adsorptive materials have different adsorptivity to different antibiotics. For different antibiotics, different adsorptive materials can be integrated in the future, and the theory can be extended to application.

Determination of Uranium using 1-(2-Pyridylazo)-2-naphthol by Adsorptive Stripping Voltammetry (1-(2-Pyridylazo)-2-naphthol을 이용한 우라늄의 흡착벗김전압전류법적 정량)

  • Kim, Kyoung Tae;Choi, Won Hyung;Lee, Jin Sik;Choi, Sung Yung
    • 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).

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