• Bulletin of the Korean Chemical Society
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• 제25권3호
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• pp.417-419
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• 2004

• 약학회지
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• 제13권2_3호
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• pp.97-100
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• 1969

As a part of an effort to find a relationship between metal chelation and its chemotherapeutic activity change for sulfa drugs, Sulfadimethoxine, Sulfamerazine Sulfamethoxy-pyridazine-Cu(II) complex compounds were studied through IR spectra.

• 한국염색가공학회지
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• 제27권1호
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• pp.62-69
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• 2015

To improve the color stability of the bioplastic containing sorghum extract, sorghum extract was chelated by a metal ion. The chelating activity was quantitatively evaluated under the various conditions. Chelation of sorghum extract by Cu(II) was determined by reaction with pyrocatechol violet, whereas Fe(II) chelation was investigated by forming complexes with ferrozine. Chelation of sorghum extract was increased rapidly with increasing concentrations of metal salt and sorghum extract. At a 0.1g/L metal salt addition level, the chelating activity of Fe(II) and Cu(II) were 66.7% and 54.2%, respectively. According to the chelation pH conditions, the sorghum extract was chelated almost 100% by Fe(II) above the pH 6.5. It was confirmed that Fe(II) was a strong chelator of sorghum extract than Cu(II). The sorghum extract chelated with metal salt exhibit higher thermal stability. The bioplastic containing chelated sorghum extract showed relatively less color change than the control.

• 한국산학기술학회논문지
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• 제8권5호
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• pp.1273-1278
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• 2007

생체내에 존재하는 효소 등의 단백질은 그 골격을 이루는 아미노산 이외에 다양한 형태로 금속 원소들과 킬레이션을 이루고, 고유한 생리활성을 나타낸다. 단백질과 금속과의 킬레이션을 체계적으로 연구하기 위하여 가수분해하여 얻은 펩타이드와 Zn(II) 이온을 반응시키고, MALDI-TOF 질량분석기로 킬레이트 반응전 후의 펩타이드의 분자량을 측정하여 킬레이트 반응 생성물을 확인하는 분석법을 개발하고자 한다.

• Bulletin of the Korean Chemical Society
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• 제5권3호
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• pp.108-112
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• 1984

Interactions between metal ions and chitosan in solution were studied by spectroscopic and viscometric measurements. $Cu^{++}$-chitosan complex exhibited an absorption band at 265 nm, whereas D-glucosamine complex showed one at 245 nm. The difference in ${\lambda}_{max}$ was attributed to the different amine to $Cu^{2+}$ ratios of the complexes, that is, 2 : 1 for chitosan and 1 : 1 for D-glucosamine. The molar absorptivities and binding constants of the complexes were evaluatatled. The binding of $Cu^{2+}$ to chitosan was cooperative near pH 5, and both intra- and intermolecular chelations depending on chitosan and $Cu^{2+}$concentrations were observed, The intermolecular chelation was stabilized by addition of salts. The cooperative intermolecular chelation of $Ni^{++}$ was also observed at pH 6.2. No significant binding of other divalent ions was observed. The reported high adsorption abilities of chitosan particles for these ions were attributed to the deposition of metal hydroxide aggregates in pores of chitosan particles rather than chelation to amine groups.

• Membrane and Water Treatment
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• 제9권3호
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• pp.137-146
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• 2018

Soil washing is one of the most frequently used remediation technologies for heavy metal-contaminated soils. Inorganic and organic acids and chelating agents that can enhance the removal of heavy metals from contaminated soils have been employed as soil washing agents. However, the toxicity, low removal efficiency and high cost of these chemicals limit their use. Given that humic substance (HS) can effectively chelate heavy metals, the development of an eco-friendly, performance-efficient and cost-effective soil washing agent using a nano-scale chelator composed of HS was examined in this study. Copper (Cu) and lead (Pb) were selected as target heavy metals. In soil washing experiments, HS concentration, pH, soil:washing solution ratio and extraction time were evaluated with regard to washing efficiency and the chelation effect. The highest removal rates by soil washing (69% for Cu and 56% for Pb) were achieved at an HS concentration of 1,000 mg/L and soil:washing solution ratio of 1:25. Washing with HS was found to be effective when the pH value was higher than 8, which can be attributed to the increased chelation effect between HS and heavy metals at the high pH range. In contrast, the washing efficiency decreased markedly in the low pH range due to HS precipitation. The chelation capacities for Cu and Pb in the aqueous phase were determined to be 0.547mmol-Cu/g-HS and 0.192mmol-Pb/g-HS, respectively.

• 분석과학
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• 제8권3호
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• pp.299-304
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• 1995

정지상으로서 N, N'-bispalmtoyl 1, 12-diaza-3, 4:9,10-dibenzo-5, 8-cyclopentadecane (hexadecyl $NtnOenH_4$)-octadecylsilanized silicas(ODS)와 이동상으로 물을 사용하여 Ba(II), Cr(II), Fe(II) 및 Cu(II)의 흡착특성을 조사하였다. 수용액상 Ba(II), Cr(II), Fe(II) 및 Cu(II)의 결합상수와 흡착도를 조사한 결과 그 순위는 Ba(II)$NtnOenH_4$-octadecylsilanized silicas(ODS)에 흡측되는 금속이온의 농도 증가는 cation chelation mechanism에 의해 설명할 수 있었다. 또한 수용액상에서 Ba(II), Cr(II), Fe(II) 및 Cu(II)이 혼합된 용액에서 Cu(II)의 분리효율이 다른 이온들에 비해서 좋게 나타남을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.243-250
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• 2006

Three novel potential metal ion chelating units have been synthesized and characterized: 5-hexylcarbamoyl-3,4-dihydroxythiophene-2-carboxylic acid methyl ester (5), 3-benzyloxy-4-hydroxythiophene-2,5-dicarboxylic acid bis-hexylamide (6), and 3,4-dihydroxythiophene-2,5-dicarboxylic acid bis-hexylamide (7). The crystal structure of 6 was obtained and suggests the presence of three distinct intramolecular hydrogen bonds, namely $[N_{amide}-H{\cdot}{\cdot}{\cdot}O]$ $[O-H{\cdot}{\cdot}{\cdot}O_{amide}]$ and $[N_{amide}-H{\cdot}{\cdot}{\cdot}S]$. Boron chelation with 5, 6 and 7 through the use of $BF_3, \;B(OH)_3 \;or \;B(OMe)_3$ was probed by $^1H$, $^{11}B$, and $^{13}C$ NMR spectroscopy. Technetium (I) chelation with 5, 6 and 7 was also studied via HPLC elutions using $[^{99m}Tc(CO)_3(OH_2)_3]^+$.

• 한국결정성장학회지
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• 제8권2호
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• pp.350-355
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• 1998

Ethylene glycol을 polymeric carrier로 사용한 새로운 화학적 세라믹 분말 제조 공정에 의하여 $(Dy_2TiO_5)$ 분말을 제조하였다. Chelation 공정의 생략에도 불구하고, 고순도의 미세한 입자를 갖는 세라믹 분말 제조가 가능함을 확인하였다. 열분석, 미세구조분석, 회절분석 등으로 분말특성을 평가하였다.

• Archives of Pharmacal Research
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• 제12권2호
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• pp.119-124
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• 1989

Cotton xanthate, which was obtained by treating cotton with carbon disulfide in alkaline solution, was treated with the solution of polyvalent metal ions to produce cotton xanthate-metal chelates. This chelation reaction was readily and simply achieved, and antimicrobial agents with suitable structures could subsequently be coupled to the chelate with ease at moderate pH values and in aqueous solution. Metal ions used in present work include Cu(II), Zn(II) and Fe(III). Tetracycline, streptomycin, neomycin and pyrithion were used as antimicrobial/antifungal agents. Antibacterial activities were measured employing ditch plate method against G(+) Staphylococcus aureus, Streptococus faecalis, and G(-) Escherichia coli, Enterobacter aerogenes, and the fungus, Aspergillus niger. All the cotton xanthate-metal-antimicrobial agent chelates exhibited activities whereas the cotton xanthate-metal chelates themselves were inactive. Considering the extensive washing procedures and results from control experiments, possibility of the involvement of physical adsorption for the binding of drugs could be excluded.